Answer:
Perimeter of the model is approximately 1 m.
Step-by-step explanation:
Given:
Scale factor = [tex]\frac{1}{32}[/tex]
Actual base length of the sailboat (b) = 8 m
Actual hypotenuse length of the sailboat (h) = 13 m
Using Pythagoras theorem, we can find the third side of the right angled sailboat. Let the third side be 'l' m. So,
[tex]h^2=b^2+l^2\\\\13^2=8^2+l^2\\\\l^2=169-64\\\\l=\sqrt{105}=10.25\ m[/tex]
Now, actual perimeter of the sailboat = Sum of all the 3 sides
Actual perimeter = 13 m + 8 m + 10.25 m = 31.25 m
Now, we know that,
Scale factor = Model dimensions ÷ Actual dimensions
So, in terms of perimeter,
Scale factor = Model perimeter ÷ Actual perimeter
[tex]\frac{1}{32}=\frac{Model\ perimeter}{31.25}\\\\Model\ perimeter=\frac{31.25}{32}=0.97\approx1\ m[/tex]
So, perimeter of the model is approximately 1 m.
Country A has twice as many workers as Country B. Country A also has twice as much physical capital, twice as much human capital, and access to twice as many natural resources as Country B. Assuming constant-returns to scale, which of the following is higher in Country A?
a. Both output per worker and productivity.
b. Output per worker but not productivity.
c. Productivity but not output per worker.
d. Neither output per worker nor productivity.
Answer: d
Step-by-step explanation: Both country A and B has equal number of workers,physical capital, human capital and access to natural resources.
Non is higher than the other.
Need help ASAP
Simplify using only positive exponents
1.) 3^2•3^4
2.) (2x^2)^-4
3.) 2x^4y^-4z^-3
————————-
3x^2y^-3z^4
Part (1) : The solution is [tex]729[/tex]
Part (2): The solution is [tex]$\frac{1}{16 x^{8}}$[/tex]
Part (3): The solution is [tex]$\frac{2 x^{2}}{3 y z^{7}}$[/tex]
Explanation:
Part (1): The expression is [tex]3^{2} \cdot3^{4}[/tex]
Applying the exponent rule, [tex]$a^{b} \cdot a^{c}=a^{b+c}$[/tex], we get,
[tex]$3^{2} \cdot 3^{4}=3^{2+4}$[/tex]
Adding the exponent, we get,
[tex]3^{2} \cdot3^{4}=3^6=729[/tex]
Thus, the simplified value of the expression is [tex]729[/tex]
Part (2): The expression is [tex]$\left(2 x^{2}\right)^{-4}$[/tex]
Applying the exponent rule, [tex]$a^{-b}=\frac{1}{a^{b}}$[/tex], we have,
[tex]$\left(2 x^{2}\right)^{-4}=\frac{1}{\left(2 x^{2}\right)^{4}}$[/tex]
Simplifying the expression, we have,
[tex]\frac{1}{2^4x^8}[/tex]
Thus, we have,
[tex]$\frac{1}{16 x^{8}}$[/tex]
Thus, the value of the expression is [tex]$\frac{1}{16 x^{8}}$[/tex]
Part (3): The expression is [tex]$\frac{2 x^{4} y^{-4} z^{-3}}{3 x^{2} y^{-3} z^{4}}$[/tex]
Applying the exponent rule, [tex]$\frac{x^{a}}{x^{b}}=x^{a-b}$[/tex], we have,
[tex]\frac{2x^{4-2}y^{-4+3}z^{-3-4}}{3}[/tex]
Adding the powers, we get,
[tex]\frac{2x^{2}y^{-1}z^{-7}}{3}[/tex]
Applying the exponent rule, [tex]$a^{-b}=\frac{1}{a^{b}}$[/tex], we have,
[tex]$\frac{2 x^{2}}{3 y z^{7}}$[/tex]
Thus, the value of the expression is [tex]$\frac{2 x^{2}}{3 y z^{7}}$[/tex]
Anyone know the answer for this problem??
Answer:
20%.
Step-by-step explanation:
I = PRT
300 = 3000*R * 0.5
300 = 1500R
R = 300 / 1500
R = 3/15 = 1/5
As a percentage it is 100 * 1/5
= 20%.
Answer: 20%
Step-by-step explanation: Notice that in this problem we're asked to find the interest rate not the interest so our answer will be a percent rate of interest.
Let's start this problem by writing the interest formula shown below.
Interest = principal · rate · time
Now we fill in the formula.
The interest earned is $300 so we substitute 300 into the formula.
The principal is the amount invested or $3,000.
We don't know the rate so we can use the variable r.
The time is 0.5 which is equivalent to 1/2
so we can substitute 1/2 in for t.
So we have the equation 300 = (3,000)(r)(1/2).
Simplifying on the right side of the equation, 3,000 · 1/2 is 1,500.
So we have 300 = 1,500r
Now to solve for r since r is being multiplied by 1,500, we need to divide by 1,500 on both side of the equation.
On the right side of the equation, the 1,500's cancel and we have r and on the left side of the equation we have 300 divided by 1,500 or 0.2.
This means that 0.2 = r.
Remember however that the interest rate is a percent so we need to change our decimal to a percent by moving the decimal point 2 places to the right to get 20%. So the interest rate is 20%.
26,) If y varies inversely as x, and y = 5 as x = 6, find y for the x-value of 10.
Answer:
3
Step-by-step explanation:
the initial statement is
y ∝ 1 /x
to convert to an equation multiply by k the constant
of variation
y = k × 1 /x = k /x
to find k use the given condition
y = 5 when x = 6
y = k/ x ⇒ k = y x = 5 × 6 = 30
y = 30 /x
when
x = 10
then
y = 30 /10 = 3
Answer: y = 3
Step-by-step explanation:
In inverse variation, as one variable increases, the other variable decreases and as one variable decreases, the other increases.
We would introduce a constant of proportionality, k. Therefore,
y = k/x
When y = 5 , x = 6
Therefore,
5 = k/6
Cross multiplying by 6, it becomes
k = 6 × 5 = 30
The expression becomes
y = 30/x
Therefore, when x is 10,
y = 30/10
y = 3
A local Walmart sells sweatpants ($7) and jackets ($14). If total sales were $6,160 and customers bought 8 times as many sweatpants as jackets, what would be the number of jackets sold?
A. 880
B. 8
C. 88
D. 8,880
E. None of these
Answer:
Option C) 88
Step-by-step explanation:
We are given the following in the question:
Unit cost of sweatpants = $7
Unit cost of jackets = $14
Let x be the number of sweatpants sold and y be the number of jackets sold.
Customers bought 8 times as many sweatpants as jackets
Then, we can write,
[tex]x = 8y[/tex]
Total sales = $6,160
[tex]7x + 14y = 6160[/tex]
Substituting the values, we get,
[tex]7(8y) + 14y = 6160\\70y = 6160\\y = 88\\x = 704[/tex]
Thus, 88 jackets were sold.
Option C) 88
A yard of lace costs w cents a yard and fabric costs $.40 more than the lace. Kimberly wants to buy one yard of lace and 2 yards of fabric. Mow much money will she need? Express your answer in terms of w.
Answer:
Step-by-step explanation:
A yard of lace costs w cents a yard and fabric costs $.40 more than the lace. This means that the cost of a yard of fabric would be
w + 0.5
Kimberly wants to buy one yard of lace and 2 yards of fabric. This means that the total amount of money that she would have to pay for the lace is is
0.4 × 1 = 0.40
Amount that she would spend on the fabric is 2(w + 0.5) = 2w + 1
Total cost would be
0.4 + 2w + 1
Final answer:
Kimberly will need a total of 3w + 80 cents to purchase one yard of lace and two yards of fabric, where w is the cost of one yard of lace in cents.
Explanation:
To calculate how much money Kimberly will need to buy one yard of lace and two yards of fabric, first we identify the cost of one yard of lace as w cents. The fabric costs $0.40 more than the lace per yard, so the cost of one yard of fabric is w cents + 40 cents. Kimberly wants to buy two yards of fabric, so we multiply the cost of one yard of fabric by 2, which gives us 2(w + 40) cents.
Adding together the cost of the lace and the two yards of fabric, we get: w + 2(w + 40). Simplifying this expression, we have: w (cost of one yard of lace) + 2w (twice the cost of lace per yard for two yards of fabric) + 80 (twice the additional cost of fabric per yard)
w + 2w + 80 cents
3w + 80 cents
Therefore, Kimberly will need a total of 3w + 80 cents to purchase one yard of lace and two yards of fabric.
In a lilac paint mixture 40% of the mixture is white paint 20% is blue and the rest is red there are four cups of blue paint used in a batch of lilac paint how many cups of white paint is used
Answer: 8 cups of white paint is used.
Step-by-step explanation:
In a lilac paint mixture 40% of the mixture is white paint 20% is blue and the rest is red. This means that the percentage of red paint in the mixture is 100 - (40 + 20) = 40%
There are four cups of blue paint used in a batch of lilac paint. This means that 20% of the total number of cups of paint used in a batch of lilac paint is 4.
Assuming that the total number of cups of paint in the mixture is x, then,
20/100 × x = 4
0.2x = 4
x = 4/0.2 = 20
Therefore, the number of cups of white paint used is
40/100 × 20 = 0.4 × 20
= 8 cups
Final answer:
In the lilac paint mixture, for every 4 cups of blue paint, which accounts for 20% of the mixture, there are 8 cups of white paint, corresponding to 40% of the mixture.
Explanation:
The question involves determining the amount of white paint used in a batch of lilac paint given that 40% of the paint mixture is white, 20% is blue, and the remainder is red. We're told that 4 cups of blue paint are used. Since blue paint represents 20% of the mixture, we can use this information to find out the total amount of the paint mixture and then calculate the amount of white paint needed.
First, find the total amount of the paint mixture by calculating the full 100% that the 4 cups of blue paint (20%) contribute to. This calculation is as follows:
Total Paint = 4 cups (20%) / 0.20Total Paint = 20 cupsNow that we know the total paint mixture is 20 cups, we can determine the amount of white paint, which is 40% of the total mixture:
White Paint = Total Paint x 40%White Paint = 20 cups x 0.40White Paint = 8 cupsTherefore, 8 cups of white paint are used in the mixture.
The apparent brightness of a star if it were viewed from a distance of 10 parsecs (32.6 light- years) is called ________.
Answer:
Absolute magnitude
Step-by-step explanation: Astronomy deals with the study of stars and other heavenly bodies. Astronomers use apparent magnitude to define how bright a star appears and shines from the earth.
The golden state bridge is 8980 feet long .For a science project , garbriel built a scale model of the bridge . How long is the model if he used the scale.1 millimeters equals 20 feet/
Answer:
449 millimeters.
Step-by-step explanation:
Each millimeter corresponds to 20 feet.
Therefore the length of the model = 8980 / 20 = 449 millimeters.
Answer:
HI! I'VE DONE THIS B4, IT IS 449 MILLIMETERS. DOES ANYONE KNOW HOW TO TURN THE CAPS BUTTON OFF? ANYWAYS, PLZ MARK BRAINLIEST
Step-by-step explanation:
Find the inverse of the function.
Y= -3/x+4
Yo sup??
y=-3/x+4
cross multiply
x+4=-3/y
x=-3/y-4
f(y)=-3/y-4
or
f(x)=-3/x-4
=-4x-3/x
The correct answer is option 4
Hope this helps.
what are the values of c and d in the matrix [[6,8],[-11,15]]-[[c+2,3],[-5,d-4]]=[[22,5],[-6,17]]
Answer:
c = -18
d = 2
Step-by-step explanation:
[[6,8],[-11,15]]-[[c+2,3],[-5,d-4]]=[[22,5],[-6,17]]
First we arrange the subtraction to clear the unknowns
- [[c+2,3],[-5,d-4]] = [[22,5],[-6,17]] - [[6,8],[-11,15]]
[[c+2,3],[-5,d-4]] = [[6,8],[-11,15]] - [[22,5],[-6,17]]
Now we solve what can be done
[[c+2,3],[-5,d-4]] = [[6-22 , 8-5],[-11+6 , 15-17]]
[[c+2,3],[-5,d-4]] = [[-16 , 3] , [-5 , -2]
we match each term with its corresponding one and we will obtain
c + 2 = -16 d - 4 = -2
c = -16 - 2 d = -2 + 4
c = -18 d = 2
Janay is constructing a triangle using wire an art project.She has 3 inches of purple wire and 7 inches of pink wire.Janay is going to buy some blue wire for the third side of her triangle
For Janay's art project, the blue wire must be longer than 4 inches and shorter than 10 inches to create a triangle. This is based on the Triangle Inequality Theorem, which states that the length of any side of a triangle should be less than the sum of the lengths of the other two sides, but more than the difference of the two sides' lengths.
Explanation:To determine how long the blue wire should be for Janay's art project, we need to understand a rule in geometry related to triangles, specifically the Triangle Inequality Theorem. This theorem states that the length of any side of a triangle must be less than the sum of the lengths of the other two sides.
Here, we have side lengths of 3 inches (purple wire) and 7 inches (pink wire), so the blue wire can be any length that is less than 3+7=10 inches, and more than |7-3|=4 inches. So the blue wire should be more than 4 inches and less than 10 inches to form a triangle.
This ensures that Janay will be able to form a valid triangle for her art project. If the length of the blue wire is less than 4 inches or greater than 10 inches, a triangle cannot be formed.
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A silicon (Φ = 7.77 × 10-19 J) surface is irradiated with UV radiation with a wavelength of 235 nm. Assume an electron was a mass of 9.11 x 10-31 kg. What is the kinetic energy of the emitted electrons?
Since a silicon (Φ = 7.77 × 10-19 J) surface is irradiated with UV radiation with a wavelength of 235 nm. Assume an electron was a mass of 9.11 x 10-31 kg, the kinetic energy of the emitted electrons is 6.9 × 10⁻²⁰ J
What is kinetic energy of emitted electron in photoelectroic effect?The kinetic energy of emitted electron in photoelectric effect is given by
K = hc/λ - Φ where
h = Planck's constant = 6.63 × 10⁻³⁴ Jsc = speed of light = 3 × 10⁸ m/s λ = wavelength of light andΦ = work function of metalSince a silicon (Φ = 7.77 × 10-19 J) surface is irradiated with UV radiation with a wavelength of 235 nm. Assume an electron was a mass of 9.11 x 10-31 kg. To determine the kinetic energy of the emitted electrons, we proceed as follows
Since the kinetic energy of the emitted electrons is
K = hc/λ - Φ
Given that
λ = 235 nm = 235 × 10⁻⁹ m andΦ = 7.77 × 10⁻¹⁹ JSo, substituting the values of the variables into the equation, we have that
K = hc/λ - Φ
K = (6.63 × 10⁻³⁴ Js × 3 × 10⁸ m/s)/235 × 10⁻⁹ m - 7.77 × 10⁻¹⁹ J
K = (19.89 × 10⁻²⁶ Jm)/235 × 10⁻⁹ m - 7.77 × 10⁻¹⁹ J
K = 0.0846 × 10⁻¹⁷ J - 7.77 × 10⁻¹⁹ J
K = 8.46 × 10⁻¹⁹ J - 7.77 × 10⁻¹⁹ J
K = 0.69 × 10⁻¹⁹ J
K = 6.9 × 10⁻²⁰ J
So, the kinetic energy is K = 6.9 × 10⁻²⁰ J
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The height of Mountain P is 1,086 feet.The height of Mountain Q is 4 times the height of Mountain P.The area model shown below represents one way to find the height of Mountain Q. What are missing values for a,b,c in the model?
Answer:
A=4000, B=80, C=24
Step-by-step explanation:
You forgot to put the correct area model, I attached it to the answer.
We have the fact that Mountain Q is 4 times the height of Mountain P. That's the "4" we have in the left side of our model. It's like having a multiplication table, next to the "4" we have "A" and upper this we have "1000", the only thing we have to do is multiplify 4*1000=4000. The next letter we have is B and below it we have "320", we divided it by 4, 320/4=80. The last letter we have is C, and is below a "6", we only have to multiplify it by 4, 6*4=24.
At the end we only sum our
A + 320 + c = 4344 (4 times the height of Mountain P).1000 + B + 6 = 1086(the height of the Mountain P).The missing values in the model for the area are:
A = 4,000
B = 80
C = 24
What is a Model?A model is a mathematical system that represents a real life concept in an easy to understand manner.
Given the model in this question, we can find the missing values as shown below:
A = 4 × 1000 = 4,000
B = 320/4 = 80
C = 4 × 6 = 24
Therefore, the missing values in the model for the area are:
A = 4,000
B = 80
C = 24
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-----40 POINTS--------
Provide the missing reasons for the proof of part of the triangle midsegment theorem.
Proof
Provide the missing reasons for the proof of part of the triangle midsegment theorem.
Given: K is the midpoint of MJ.
L is the midpoint of NJ.
Prove: MN = 2KL
The complete answer is attached in the diagram below.
The complete answer for the missing reasons is attached below in the diagram.
Please check the figure.
Keywords: statement, proof, reason
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A paper company needs to ship paper to a large printing business. The paper will be shipped in small boxes and large boxes. Each small box of paper weighs 40 pounds and each large box of paper weighs 70 pounds. A total of 20 boxes of paper were shipped weighing 1220 pounds altogether. Write a system of equations that could be used to determine the number of small boxes shipped and the number of large boxes shipped. Define the variables that you use to write the system.
Answer: The system of equations required is
x + y = 20
40x + 70y = 1220
Step-by-step explanation:
Let x represent the number of small boxes of paper shipped and
Let y represent the number of large boxes of paper shipped.
A total of 20 boxes of paper were shipped. This is expressed as
x + y = 20
Each small box of paper weighs 40 pounds and each large box of paper weighs 70 pounds. The total weight of the large and small boxes of paper that were shipped is 1220 pounds altogether. This is expressed as
40x + 70y = 1220
We define x as the number of small boxes and y as the number of large boxes. The first equation, x + y = 20, is based on the total number of boxes. The second equation, 40x + 70y = 1220, is based on the total weight of the boxes.
Explanation:We need to find a system of equations that represents the given situation. We will use two variables. Let's say x represents the number of small boxes and y represents the number of large boxes for your problem.
The first equation can be based on the total number of boxes, which is 20. So, the equation is: x + y = 20.
The second equation will be based on the total weight of the boxes, which is 1220 pounds. A small box weighs 40 pounds and a large box weighs 70 pounds. So, the equation will be: 40x + 70y = 1220.
So, we have the system of equations:
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The probability you'll see a falling star in the sky over the course of one hour is 0.44. What's the probability you'll see one over half an hour?
Answer:
Probability so see one falling star over half an hour is 0.25
Step-by-step explanation:
An hour can be taken as two half hours so we can write the probability to see a falling star as
(1-P)*(1-P) = 1 - 0.44
( 1 - P )² = 0.56
1 - P = [tex]\sqrt{0.56}[/tex]
P = 1 - [tex]\sqrt{0.56}[/tex]
P = 0.25
The temperature is 71 °F at 2:00 in the afternoon. If the temperature drops 8 °F every hour after that, what is the temperature at 6:00 in the evening?
Answer = _____ F
Answer:
The answer is 39 degrees by 6:00 in the evening.
Step-by-step explanation:
Since it is 2:00 in the afternoon and there is 4 hours, with 8 degrees dropping every hour, 8 times 4 equals 32, so 71 degrees minus 32 degrees is 39 degrees.
Answer: the temperature at 6:00 in the evening is 39°F
Step-by-step explanation:
If the temperature drops 8 °F every hour after that, then the rate is linear and the rate at which the temperature is decreasing is in arithmetic progression. The formula for determining the nth term of an arithmetic sequence is expressed as
Tn = a + (n - 1)d
Where
a represents the first term of the sequence.
d represents the common difference.
n represents the number of terms in the sequence.
From the information given,
a = 71 °F
d = - 8 °F (since it is decreasing)
n = 5 (2pm to 6pm)
We want to determine the value of the 5th term, T5. Therefore,
T5 = 71 - 8(5 - 1)
T5 = 71 - 32 = 39
Hank and debra each own two milking cows. One day, they milked their cows and compared the amount of milk the cows prodyce in that one day. How many more gallons of milk did debras two cowsbprodyce on that day compared to hanls two cows?
Debra's cows produced [tex] 2 \frac{7}{24}[/tex] more gallons than Hank's cows.
Hank's cows :
4¾ + 4⅛ = 8⅞Debra's Cows :
5½ + 5⅔ = 11⅙The difference in amount of Milk produced :
Sum of Debra's cow - Sum of Hank's cows
Now we have:
11⅙ - 8⅞
67/6 - 71/8 = (536 - 426) / 48
67/6 - 71/8 = 110/48
110/48 = [tex] 2 \frac{7}{24}[/tex]
Hence, Debra's cows produced [tex] 2 \frac{7}{24}[/tex] more gallons than Hank's cows.
Peter answered 15 questions on a quiz and obtained 29 points. If 3 points were given for each correct answer and one point deducted for each wrong answer, how many questions did Peter answer correctly?
Final answer:
By setting up an equation with x representing the number of correct answers, we find that Peter answered 11 questions correctly on his quiz.
Explanation:
To determine how many questions Peter answered correctly on his quiz, we first need to set up an equation to represent the situation. Let's let x be the number of questions Peter got right, and since he answered 15 questions in total, it means he got (15 - x) questions wrong. Since he gets 3 points for each correct answer and loses 1 point for each wrong answer, we can write the equation as:
3x - (15 - x) = 29
Now, we will solve for x:
3x - 15 + x = 29
4x - 15 = 29
4x = 29 + 15
4x = 44
x = 44 / 4
x = 11
So, Peter answered 11 questions correctly.
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Koji is installing a rectangular window in an office building. The window is 823 feet wide and 534 feet high.
The formula for the area of a rectangle is A=bh.
What is the area of the window?
Enter your answer as a mixed number in simplest form in the box.
$$
a
ft2
?
? _
?
The area would be 8 2/3* 5 3/4 which according to my calculator is 49 5/6
So the area is 49 5/6 ft^2.
Hope this helped!
The cylinder coffee cup has a radius of 1.8 inches and a height of 4 inches. Find the surface area of the coffee cup, not including the handle. Round to the nearest tenth
Answer:
Step-by-step explanation:
The formula for determining the total surface area of a cylinder is expressed as
Total surface area = 2πr² + 2πrh
Where
r represents the radius of the cylinder.
h represents the height of the cylinder.
π is a constant whose value is 3.14
Assuming that the cylindrical cup is open at the top, the formula becomes
Area = πr² + 2πrh
From the information given,
Radius = 1.8 inches
Height = 4 inches
Therefore, the surface area of the coffee cup is
(3.14 × 1.8²) + (2 × 3.14 × 1.8 × 4)
= 10.1736 + 45.216
= 55.4 inches² to the nearest tenth.
Answer:
55.4 :))
Step-by-step explanation:
A grocery store has 12 cartons of yogurt for sale, of which 3 are raspberry. What is the probability that a randomly selected carton of yogurt will be raspberry?
Answer:
The answer to your question is the probability to select a yogurt of raspberry is 1/4 or 25%.
Step-by-step explanation:
Data
Number of cartons = 12
Number of cartons of raspberry = 3
To solve this problem, just use the formula of probability and simplify it to get the result.
Formula
P(A) = [tex]\frac{Number of favorable outcomes to A}{Total number of outcomes}[/tex]
Substitution
P(A) = 3/12
Simplification
P(A) = 1/4 or 25%
Rosa earns $120 per week tutoring math. Each week, she puts $36 from her paycheck in her bank account to save for college. Rosa wants to know what percent of her earnings she saves.
Final answer:
Rosa saves 30% of her weekly earnings for college, which is calculated by dividing the amount saved ($36) by her total weekly earnings ($120) and then multiplying by 100%.
Explanation:
To determine the percentage of her earnings that Rosa saves, we will use the formula for calculating percentage: Percentage saved = (Amount saved ÷ Total earnings) × 100%.
First, we identify the total earnings and the amount saved: Rosa's total weekly earnings are $120, and she saves $36 each week.
Next, we calculate the percentage: Percentage saved = ($36 ÷ $120) × 100% = 0.3 × 100% = 30%.
Therefore, Rosa saves 30% of her weekly earnings for college.
Lisa wants to use her calculator to square a two-digit positive integer, but she accidentally enters the tens digit incorrectly. When she squares the number entered, the result is 2340 greater than the result she would have gotten had she correctly entered the tens digit. What is the sum of the two-digit number Lisa entered and the two-digit number she meant to enter?
Answer:
78
Step-by-step explanation:
You want to know the sum of two 2-digit numbers such that one differs from the other by a multiple of 10, and the difference of their squares is 2340.
Difference of squaresThe difference of squares is the product of the sum and difference of the two numbers. Here, the difference must be a multiple of 10, so we want factorizations of 2340 that have a multiple of 10 as a factor. These are ...
2340 = 10(234) = 20(117) = 30(78)
where the first factor (the difference) is less than the second factor (the sum).
The sum of two 2-digit numbers cannot be more than 200, and it must be even if they both have the same units digit. The only viable product from the above list is 30 × 78, where 30 is the difference of the numbers and 78 is their sum.
The sum of the numbers is 78.
__
Additional comment
The two numbers are 54 and 24. The difference of their squares is ...
2916 -576 = 2340
Difference of squares: a² -b² = (a -b)(a +b).
The radius of the earth is 4000 miles. How fast is someone on the equator moving compared to someone at the north pole due to daily rotation of the Earth (in miles per hour)?
Answer: speed at the equator =
1047.33 miles per hour
Step-by-step explanation:
The radius of earth is 4000miles
The earth rotates on its axis, hence we calculate the circumference at the equator
Circumference, C = 2 π R
C = 2 x 3.142 x 4000miles
C = 25,136 miles
Since the total time of one complete rotation about it's axis is 24hours
Hence, the speed at the equator is
speed = 25,136/24 = 1047.33 miles per hour
The speed of the person on the equator due to daily rotation of the earth is;
Speed = 1047.221 miles per hour
We are told that the radius of the earth is; R = 4000 miles.Formula for circumference is;
C = 2πR
Thus;
C = 2 × π × 4000miles
C = 25,132.74 miles
C ≈ 25133 miles
Now, the time it takes for the earth to complete one full rotation about it's axis is 24 hours.
We know that formula for speed is;
speed = distance/time
Thus;
Speed on the equator is;
speed = 25133/24 = 1047.221 mph
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The cost of controlling emissions at a firm goes up rapidly as the amount of emissions reduced goes up. Here is a possible model: C(x, y) = 7,000 + 100x2 + 50y2 where x is the reduction in sulfur emissions, y is the reduction in lead emissions (in pounds of pollutant per day), and C is the daily cost to the firm (in dollars) of this reduction. Government clean-air subsidies amount to $500 per pound of sulfur and $100 per pound of lead removed. How many pounds of pollutant should the firm remove each day in order to minimize net cost (cost minus subsidy)?
Answer:
2.5 pounds pounds of sulfur and 1 pound of lead should be removed each day in order to minimize net cost.
Step-by-step explanation:
Given model of cost:
[tex]C(x, y) = 7,000 + 100x^2 + 50y^2[/tex]
Government clean-air subsidies amount for sulfur = 500 $/pound
Government clean-air subsidies amount for lead = 100 $/pound
Subsidies amount for x pounds of sulfur = x500 $
Subsidies amount for y pounds of lead= y100 $
Model of subsidy amount :
[tex]S(x,y)=500x+100y[/tex]
Net cost(N) = Cost - Subsidy = C(x,y)-S(x,y)
[tex]N=7,000 + 100x^2 + 50y^2-500x-100y[/tex]..[1]
Differentiating above [1] in with respect to dx :
[tex]\frac{dN}{dx}=\frac{7,000 + 100x^2 + 50y^2-500x-100y}{dx}[/tex]
[tex]\frac{dN}{dx}=200x-500[/tex]..[2]
Putting [tex]\frac{dN}{dx}=0[/tex]:
[tex]0=200x-500[/tex]
x = 2.5
Now taking second derivative of [2]:
[tex]\frac{d^N}{dx^2}=200[/tex]
[tex]\frac{d^N}{dx^2}>0[/tex] (minima)
Differentiating above [1] in with respect to dy :
[tex]\frac{dN}{dy}=\frac{7,000 + 100x^2 + 50y^2-500x-100y}{dy}[/tex]
[tex]\frac{dN}{dy}=100y-100[/tex]..[3]
Putting [tex]\frac{dN}{dy}=0[/tex]:
[tex]0=100y-100[/tex]
y = 1
Now taking second derivative of [3]:
[tex]\frac{d^N}{dy^2}=100[/tex]
[tex]\frac{d^N}{dy^2}>0[/tex] (minima)
2.5 pounds pounds of sulfur and 1 pound of lead should be removed each day in order to minimize net cost.
The amounts of sulfur and lead the firm should remove are 2.5 pounds and 1 pound respectively to minimize the net cost.
Given to us
cost of controlling emissions, C(x, y) = 7,000 + 100x² + 50y²
amount to $500 per pound of sulfur
$100 per pound of lead removed
What is the net cost of the firm?We know that the net cost can be written as,
T(x, y) = 7,000 + 100x² + 50y² -500x -100y
where x and y is the amount of sulfur and lead emission reduced respectively.
What is the minimum amount of sulfur that should be removed?
To find the minimum of x differentiate the value of net cost with respect to x,
[tex]\dfrac{dT}{dx} = \dfrac{ 7,000 + 100x^2 + 50y^2 -500x -100y}{dx}[/tex]
[tex]= \dfrac{ 7,000 + 100x^2 + 50y^2 -500x -100y}{dx}\\\\= 0+ 100(2x) + 0 + 500 + 0\\\\ = 200x+500[/tex]
Substitute against 0, to get the minimum value of x,
0 = 200x+500
x = 2.5
Differentiate again,
[tex]\dfrac{d^2T}{dx^2} = \dfrac{d(200x+500)}{dx}[/tex]
[tex]=200+0[/tex]
As the value of differentiation is positive, therefore, the slope of the function will be going towards the positive.
What is the minimum amount of Lead that should be removed?To find the minimum of y differentiate the net cost with respect to y,
[tex]\dfrac{dT}{dy} = \dfrac{ 7,000 + 100x^2 + 50y^2 -500x -100y}{dy}[/tex]
[tex]= 0+0+50(2y)-100\\\\=100y-100\\\\=100(y-1)[/tex]
Substitute against 0 to get the minimum value of y,
0 = 100(y-1)
y = 1
Differentiate again,
[tex]\dfrac{d^2T}{dy^2} = \dfrac{d(100y-100)}{dy}[/tex]
[tex]=100[/tex]
As the value of differentiation is positive, therefore, the slope of the function will be going towards the positive.
Hence, the amount of sulfur and lead the firm should remove is 2.5 pounds and 1 pound respectively to minimize the net cost.
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We have three fair coins, each of which has probability 1/2 of having a heads outcome and a tails outcome. The experiment is to flip all three coins and observe the sequence of heads and tails. For example, outcome HTH means coin 1 was heads, coin 2 was tails, coin 3 was heads. Note that there are 8 total outcomes, and we assume that each one is equally likely. What is the probability that the outcome has at least two consecutive heads in the sequence?
Answer: 3/8
Step-by-step explanation:
Firstly, let's look at the possible outcome when 3 coins are tossed.
If two coins are first tossed, the possible outcome will be,
{HH, HT, TH, TT}
if one more coin is tossed together with the two to make it 3coins, the possible outcome will be gotten by matching the H and T of the third coin with the set of sample space above to give us,
S = {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT}
This gives a total sample space of 8.
Outcomes that has at least two consecutive heads in the sequence are {HHH, HHT, THH} which is the possible outcome i.e 3
Probability that the outcome has at least two consecutive heads in the sequence will be;
Possible outcome/total outcome
= 3/8
Students are selling raffle tickets for a school fundraiser. They collect $25 for every 10 raffle tickets sold. Rain equation that reflects the relationship between m and r
Answer: m= $25/10 r
Step-by-step explanation:
Let m= money
r= raffle ticket
Then according to the statement
m= $25 for 10 tickets
so 10 tickets= $25
Or the equation goes,
m= $25/10 r
Suppose the age of people in a certain population are distributed normally with a mean of 37.5 years and standard deviation of 6.2 years. What is the probability of randomly selecting a person who is over 45 years old given that they are older than 40.
Answer:
[tex] P(X>45 | X>40)= \frac{P(X>45 \cap X>40)}{P(X>40)}= \frac{P(X>45)}{P(X>40)}= \frac{0.113}{0.343}= 0.329[/tex]
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the age of a population, and for this case we know the distribution for X is given by:
[tex]X \sim N(37.5,6.2)[/tex]
Where [tex]\mu=37.5[/tex] and [tex]\sigma=6.2[/tex]
We are interested on this probability:
[tex] P(X>45 | X>40)= \frac{P(X>45 \cap X>40)}{P(X>40)}= \frac{P(X>45)}{P(X>40)}[/tex]
We can begin finding [tex] P(X>40)[/tex] using the z score formula given by:
[tex] z = \frac{a-\mu}{\sigma}[/tex]
Using this formula we have:
[tex] P(X>40)= P(Z>\frac{40-37.5}{6.2}) = P(Z>0.403)[/tex]
And using the complement rule and the normal standard table or excel we have this:
[tex]P(Z>0.403)=1-P(Z<0.403)= 1-0.657= 0.343[/tex]
Now we can find [tex] P(X>45)[/tex] using the z score formula given by:
[tex] z = \frac{a-\mu}{\sigma}[/tex]
Using this formula we have:
[tex] P(X>45)= P(Z>\frac{45-37.5}{6.2}) = P(Z>1.210)[/tex]
And using the complement rule and the normal standard table or excel we have this:
[tex]P(Z>1.210)=1-P(Z<1.210)= 1-0.887= 0.113[/tex]
And replacing into our original probability we got:
[tex] P(X>45 | X>40)= \frac{P(X>45 \cap X>40)}{P(X>40)}= \frac{P(X>45)}{P(X>40)}= \frac{0.113}{0.343}= 0.329[/tex]