If 60% of a radioactive element remains radioactive after 400 million​ years, then what percent remains radioactive after 500 million​ years? What is the​ half-life of this​ element?

Answers

Answer 1
Son this is too hard and I am a professor in a University.
Answer 2

The half-life of the element is approximately 542.78 million years.

To find out what percent of the radioactive element remains after 500 million years, we can use the exponential decay formula for radioactive decay:

[tex]\[ N(t) = N_0 \times e^{-kt} \][/tex]

Where:

- [tex]\( N(t) \)[/tex] is the amount of radioactive material remaining at time \( t \)

- [tex]\( N_0 \)[/tex] is the initial amount of radioactive material

- k is the decay constant

- t is the time elapsed

Given that 60% of the radioactive element remains after 400 million years, we know that [tex]\( N(t) = 0.60N_0 \)[/tex]  when [tex]\( t = 400 \)[/tex] million years. We also know that [tex]\( N_0 \)[/tex] represents the initial amount of radioactive material, which will cancel out when we're finding the ratio of remaining material, so we don't need its exact value.

Substituting these values into the exponential decay formula:

[tex]\[ 0.60N_0 = N_0 \times e^{-400k} \][/tex]

We can simplify this to find the decay constant k:

[tex]\[ 0.60 = e^{-400k} \][/tex]

Taking the natural logarithm (ln) of both sides to solve for k:

[tex]\[ \ln(0.60) = -400k \][/tex]

[tex]\[ k = \frac{\ln(0.60)}{-400} \][/tex]

Using this value of k, we can find out what percent of the radioactive element remains after 500 million years:

[tex]\[ N(500) = N_0 \times e^{-500k} \][/tex]

[tex]\[ N(500) = N_0 \times e^{-500 \times \frac{\ln(0.60)}{-400}} \][/tex]

Now, to find the half-life of the element, we know that the half-life [tex](\( T_{\frac{1}{2}} \))[/tex] is the time it takes for the amount of radioactive material to decrease by half. In other words, when [tex]\( N(t) = \frac{1}{2}N_0 \),[/tex] we have:

[tex]\[ \frac{1}{2}N_0 = N_0 \times e^{-kT_{\frac{1}{2}}} \][/tex]

[tex]\[ \frac{1}{2} = e^{-kT_{\frac{1}{2}}} \][/tex]

[tex]\[ \ln\left(\frac{1}{2}\right) = -kT_{\frac{1}{2}} \][/tex]

[tex]\[ T_{\frac{1}{2}} = \frac{\ln(2)}{k} \][/tex]

Now, we can calculate both the percentage remaining after 500 million years and the half-life of the element using the calculated value of k. Let's do that.

First, let's calculate the value of \( k \):

[tex]\[ k = \frac{\ln(0.60)}{-400} \][/tex]

[tex]\[ k ≈ \frac{-0.5108}{-400} \][/tex]

[tex]\[ k = 0.001277 \][/tex]

Now, let's use this value of k to find out what percent of the radioactive element remains after 500 million years:

[tex]\[ N(500) = N_0 \times e^{-500k} \][/tex]

[tex]\[ N(500) = N_0 \times e^{-500 \times 0.001277} \][/tex]

[tex]\[ N(500) ≈ N_0 \times e^{-0.6385} \][/tex]

Now, let's find out what percent this is of the original amount [tex](\( N_0 \))[/tex]:

[tex]\[ \frac{N(500)}{N_0} = e^{-0.6385} \][/tex]

[tex]\[ \frac{N(500)}{N_0} ≈ 0.5274 \][/tex]

So, approximately 52.74% of the radioactive element remains after 500 million years.

Now, let's calculate the half-life of the element:

[tex]\[ T_{\frac{1}{2}} = \frac{\ln(2)}{k} \][/tex]

[tex]\[ T_{\frac{1}{2}} = \frac{\ln(2)}{0.001277} \][/tex]

[tex]\[ T_{\frac{1}{2}} = \frac{0.6931}{0.001277} \][/tex]

[tex]\[ T_{\frac{1}{2}} = 542.78 \text{ million years} \][/tex]

So, the half-life of the element is approximately 542.78 million years.


Related Questions

A guy walks into the store and steals $100 bill from the register without the owner’s knowledge. He comes back 5 minutes later and buys $70 worth of goods with the $100 bill. The owner gives him back $30 in change. How much money did the owner lose?

Answers

the answer is $100
first the guy steals $100 from the owner. Therefore that $100 is a direct loss for the owner. 
the same guy comes and pays $100 for goods worth $70. and the balance is paid back to the guy. 
So the owner gets 100 and pays back 30 and gives goods worth 70. Therefore that transaction is cancelled as the amounts have been paid and no net effect with that transaction . the owner gets 70 for the goods he sold so that transaction wont lose his money. the fact that the guy paid for the bill with the money he stole isn't relevant here as the transaction has been completed
so the only loss for the owner is the $100 the guy stole at first 
answer is $100

Answer:

The  money that owner loses is:

                          $ 100

Step-by-step explanation:

Since, the guy walks into the store  and steals $100 bill from the register without the owner’s knowledge.

Again he comes back with the bill and buys $70 worth of goods with the $100 bill. The owner gives him back $30 in change.

This means that the loss that the owner gets at the starting is recovered as the bill is returned back to the owner and the only loss that is remaining is the cost of the goods that he buy (i.e. $ 70 ) and cost that owner returned him (i.e. $ 30)

             Hence, the total loss of the owner is:

             $ 70+$ 30=$ 100

what is 0.79 as a fraction in simplest form

Answers

79/100 is the simplest form
0.79 = 79/100. I don't believe you can simplify past this point because 79 is a prime number

cos(2θ) + 7 cos(θ) = 8

Answers

This pretty hard i really don't know man sorry

Zoe's pizza cost $12.99. She gave a tip of $2.00.

What percent did Zoe leave as a tip?

will offer 16 points if in 60 seconds or less plz

Answers

She left a 15 % tip I hope this helps u :D

Answer:

She left a 15% tip.

Step-by-step explanation:

Just do $10.99 (The original price, I believe.) and then the tip she gave. ($2.00)

And turn it into a percentage.


I know the other person already answered, 50% credits to them, because they only gave the "Answer:" part. (No offense if you're reading this.)


Hope this helped, and enjoy the little pun!

"The other person already answered 50%"


An artist sells 4 paintings for $20 each, 4 sculptures for $60 each, and 4 photographs for $10 each at her art show. How much money does the artist make on these sales in all?

Answers

for 4 painting she sells, $80. For 4 sculptures she sells $240. For 4 photographs she sells $40. Overall, she gains $760 on these sales.
for 4 painting she sells, $80. For 4 sculptures she sells $240. For 4 photographs she sells $40. Overall, she gains $760 on these sales

The marginal cost function of producing q mountain bikes is Upper C Superscript prime Baseline left-parenthesis q right-parenthesis equals StartFraction 600 Over 0.3 q plus 5 EndFraction. (a) If the fixed cost in producing the bicycles is dollar-sign 2300, find the total cost to produce 30 bicycles. Enter an answer to two decimal places. dollar-sign 4359.23 (b) If the bikes are sold for dollar-sign 220 each, what is the profit (or loss) on the first 30 bicycles? Enter an answer to two decimal places. dollar-sign 2240.77 (c) Find the marginal profit on the 31st bicycle. Enter an answer to two decimal places. dollar-sign

Answers

MArginal cost is the adjustment in all out cost that emerges when the amount created changes by one unit.(In another word subordinate of cost wrt unit) 
So we coordinate to get Cost work 
∫30 600/0.3q+5 (dq) 0
we get 9798.66 from joining. 
We add that to settle cost 2059.23+2200=4259.24 
So 4259.24 is the cost. 
Income from offering the bicycle is 205*30=6150 
and Profit=Revenue-Cost 
6150 - 4259.24=1890.76 
Presently Marginal Profit 
MArginal benefit is the term used to allude to the contrast between the minor cost the peripheral income for delivering one extra unit of creation. 
Marginal Profit=Marginal Revenue-Marginal Cost 
Marginal Cost=600/0.3q+5. 
We should connect to 31 to get 41.958 
Revenue= 205q 

Marginal rev=205 
Marginal Profit = 205-41.958=163.042

The male Cuban tree frog is about 2/5 the size of the female Cuban tree frog. The average size of the female Cuban tree frog is 6 inches. what is he size of the male cuban tree frog?

Answers

I'm pretty sure the male is 2 2/5 inches.

The size of the male Cuban tree frog is 2 2/5 inches.

Given that, the male Cuban tree frog is about 2/5 the size of the female Cuban tree frog. The average size of the female Cuban tree frog is 6 inches.

We need to find the size of the male Cuban tree frog.

How to multiply fractions with whole numbers?

Multiplying fractions with whole numbers is an easy concept. We just need to convert the whole number into a fraction by writing 1 as the denominator and writing the whole number as the numerator. Then it is multiplied by the given fraction. After multiplying these, the final result should be in the form of a proper fraction or a mixed fraction.

Now, 2/5 × 6

=12/5

=2 2/5

Therefore, the size of the male Cuban tree frog is 2 2/5 inches.

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Which of these numbers is composite? 29, 41, 47, 82, 89

Answers

Composite is the opposite of prime.

82 is a composite number.
Its 82 cause its an even number.




It is observed that 55.50 mL of water at 20°C completely fills a container to the brim. When the container and the water are heated to 60°C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container? (b) What is the most likely material of the container? Density of water at 60°C is 0.98324 g/mL.






Answers

Final answer:

The coefficient of volume expansion of the container is approximately 0.000161/°C. Based on this, the container is most likely made from a material with similar coefficient value, such as Pyrex glass.

Explanation:

The first thing to note is that the change in volume of the water is equal to the volume of the water that was lost through evaporation when the water and its container were heated. This volume can be found by dividing the amount of water lost (0.35g) by its density at 60° C (0.98324 g/mL), giving a volume loss of about 0.356 mL.

The coefficient of volume expansion of the container can be calculated using the formula ΔV/V0 = β ΔT, where ΔV is the change in volume, V0 is the initial volume, β is the coefficient of volume expansion, and ΔT is the change in temperature. Solving for β gives, β = ΔV / (V0 * ΔT) = 0.356 mL / (55.50 mL * 40C) gives approximately 0.000161/°C.

Material of the container can then be inferred based on its coefficient of volume expansion. The value of β is in the order of 10^-5/°C which indicates that the most likely material options are glass or metal, as these materials have coefficients of volume expansion in that range. Of these, Pyrex glass has a value that is closest to the calculated coefficient of volume expansion, around 0.000032/°C.

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x+3y-2z=10, -x-2y+z=-7, 3x+9y-5z=28

Answers

hmm
what you do is try to eliminate 1 variable in 2 equaions first
we can elminate x's in first and 2nd equation

add first and 2nd equation
x+3y-2z=10
-x-2y+z=-7 +
0x+y-z=3
y-z=3


multiply 2nd equation by 3 and add to last one
-3x-6y+3z=-21
3x+9y-5z=28 +
0x+3y-2z=7

3y-2z=7

we now have
y-z=3
3y-2z=7
multiply first equation by -2 and add to 2nd

-2y+2z=-6
3y-2z=7 +
y+0z=1
y=1

now we can sub back
y-z=3
1-z=3
minus 1
-z=2
times -1
z=-2

sub baack into any equation
x+3(1)-2(-2)=10
x+3+4=10
x+7=10
minus 7
x=3

x=3
y=1
z=-2
(3,1,-2)

  
[tex]\displaystyle \\ ~~~~x+3y-2z=10 ~~~~~(E_1)\\ -x-2y+z=-7 ~~~~~(E_2)\\ ~~3x+9y-5z=28~~~~~(E_3) \\ \text{- - - - - } \\ E_1 + E_2 ~~\Longrightarrow~~y - z = 3 \\ \\ -3 \times E_1 + E3 ~~\Longrightarrow~~ z = -2 \\ \\ \Longrightarrow\Longrightarrow\Longrightarrow \\ \\ y-z=3\\ z = \boxed{-2}\\ \text{- - - - - }\\ y-(-2)=3\\ y+2=3\\ y =3-2=\boxed{1}\\ \text{- - - - - }\\ x+3y-2z=10\\ x+3\cdot 1-2\cdot (-2)=10\\ x+3+4=10\\ x+7=10\\ x= 10 - 7 = \boxed{3}[/tex]



In a bag, a child has 325 coins worth $19.50. There were three types of coins: pennies, nickels, and dimes. If the bag
contained the same number of nickels as dimes, how many of each type of coin was in the bag?

Answers

there were 125 nickels, 125 dimes, and 75 pennies

The number of pennies, nickels, and dimes will be 227, 49, and 49, respectively.

What is the solution to the equation?

The allocation of weights to the important variables that produce the calculation's optimum is referred to as a direct consequence.

In a pack, a kid has 325 coins worth $19.50. There were three kinds of coins: pennies, nickels, and dimes. In the event that the pack contained a similar number of nickels as dimes.

Let 'x' be the number of dimes and nickels and 'y' be the number of pennies. Then the equations are given as,

x + x + y = 325

2x + y = 325           ....1

0.1x + 0.25x + 0.01y = 19.50

0.35x + 0.01y = 19.50        ...2

From equations 1 and 2, then we have

0.35x + 0.01(325 - 2x) = 19.50

0.35x + 3.25 - 0.02x = 19.50

0.33x = 16.25

x = 49

Then the value of 'y' will be given as,

2(49.24) + y = 325

y = 227

The number of pennies, nickels, and dimes will be 227, 49, and 49, respectively.

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The cost of a ski-lift ticket is $31.how much will 17 tickets cost?

Answers

31 x 17 = 527
answer 527
If each ticket costs $31 dollars, then 17 tickets would cost $527 dollars (31x17+527)

someone came into my shop and stole $100.00 from the register without my knowledge. The person came back in with the same $100.00 five minutes later and he bought $70.00 worth of items and gave him back $30.00 in change. How much money did I lose?

Answers

Let's do this step by step, we know that the guy steals $ 100 So it would be - $ 100 for the store. The men buy $ 70 merchandise WITH THE MONEY THAT HE STOLE, but the money that he stole CAME BACK to the store So up to this poin, : - $ 100 + $100 - $ 70 = - $ 70 for the store After that , the store give $ 30 cash back, So in the and : - $ 70 - $30 = - $ 100 lost for the store

the area of a rectangle is 256.5m2. if the length is 18m, what is the perimeter of the rectangle

Answers

256.5/18= 14.25

(14.25x2)+(18x2)= 64.5m

Perimeter of the rectangle is 64.5 m

Further explanation

To solve the above questions, we need to recall some of the formulas as follows:

Area of Rectangle = Length × Width

Perimeter of Rectangle = 2 × ( Length + Width )

Let us now tackle the problem !

Given:

Area of Rectangle = A = 256.5 m²

Length of Rectangle = L = 18 m

Unknown:

Perimeter of Rectangle = P = ?

Solution:

This problem is about Area and Perimeter of Rectangle.

Let's find the width of Rectangle.

[tex]\texttt{Area of Rectangle} = \texttt{Length} \times \texttt{Width}[/tex]

[tex]256.5 = 18 \times \texttt{Width}[/tex]

[tex]\texttt{Width} = 256.5 \div 18[/tex]

[tex]\texttt{Width} = \boxed {14.25 ~ \texttt{m}}[/tex]

Let's find the perimeter of Rectangle.

[tex]\texttt{Perimeter of Rectangle} = 2 (\texttt{Length} + \texttt{Width})[/tex]

[tex]P = 2 ( L + W )[/tex]

[tex]P = 2 ( 18 + 14.25 )[/tex]

[tex]P = 2 ( 32.25 )[/tex]

[tex]P = \boxed {64.5 ~ \texttt{m}}[/tex]

Learn moreThe perimeter of a polygon : https://brainly.com/question/6361596The perimeter of a rectangle : https://brainly.com/question/7619923The perimeter of a triangle : https://brainly.com/question/2299951

Answer details

Grade: College

Subject: Mathematics

Chapter: Two Dimensional Figures

Keywords: Perimeter, Area , Square , Rectangle , Side , Length , Width

Jason scored 14,568 points playing a video game. The all-time high score is 22,401 points. How much greater is the all-time high score than Jason's score?

Answers

The problem is asking you to find the difference between his score and the highest score. This is just a subtraction problem.

22,401-14,568=7,833
subtract 22,401-14,568= 7833

2cos^2x+cosx-1=0
Find the degree solutions

Answers

2cos²x+cos x-1=0

cos x=t

2t²+t-1=0

t=[-1⁺₋√(-1+8)]/2=(-1⁺₋3)/4
We have two possible set solutions:
First set solutions.
t₁=(-1-3)/2=-4/4=-1   
cos x=-1  ⇒x=cos⁻¹ (-1)=π +2kπ    or     180º+360ºk    (k=(...-2,-1,0,1,2...)

Second set solutions:
t₂=(-1+3)/4=2/4=1/2

cos x=1/2  ⇒ x=cos⁻¹ 1/2=π/3+2kπ   U   5π/3+ 2kπ   or
60º+360ºK  U 300º+360ºK        (k=...-2,-1,0,1,2,...)

solutions: first set solutions U second set solutions:

Answer in radians : π +2kπ U π/3+2kπ U 5π/3+ 2kπ   (k=...-1,0,1,...)
Answer is degrees: 180º+360ºk U 60º+360ºK  U 300º+360ºK        (k=...-2,-1,0,1,2,...)

The primary solutions in degrees are x = 60°, 180°, and 300°.

We need to solve the equation 2cos²(x) + cos(x) - 1 = 0 and find the degree solutions.

Let's solve this step-by-step:

First, let u = cos(x). The equation becomes 2u² + u - 1 = 0.This is a quadratic equation in u. Solve it using the quadratic formula: u = [tex]\frac{-b \pm \sqrt{b^2 - 4ac}}{ 2a}[/tex]Here, a = 2, b = 1, and c = -1. Substitute these values into the quadratic formula:
[tex]u = \frac{-1 \pm \sqrt{1^2 - 4(2)(-1)}}{ (2 * 2)}[/tex]
u = [-1 ± √(1 + 8)] / 4
u = [-1 ± √9] / 4
u = [-1 ± 3] / 4This gives us two solutions: u = 1/2 and u = -1.Recall u = cos(x):
cos(x) = 1/2 leads to x = 60° and x = 300°
cos(x) = -1 leads to x = 180°Thus, the solutions to the equation 2cos²(x) + cos(x) - 1 = 0 in degrees are x = 60°, 180°, and 300°.

the formula for glue says to add 60 ml of hardener to each container of resin. How much hardener should be added to 19 containers of resin?

Answers

19x60=1140
19 containers of resin with 60 ml of hardener each so the total is 1140 ml of hardener.

Answer

Find out the how much hardener should be added to 19 containers of resin .

To prove

Let us assume that the hardener should be added to 19 containers of resin be x .

As given

The formula for glue says to add 60 ml of hardener to each container of resin.

than the equation become

x = 19 × 60

x =  1140 ml

Therefore the  1140 ml hardener should be added to 19 containers of resin .

Hence proved

A university student center sells 1,600 cups of coffee per day at a price of $2.40. a market survey shows that for every $0.05 reduction in price, 50 more cups of coffee will be sold. how much should the student center charge for a cup of coffee in order to maximize revenue?

Answers

2.00 would be the best price to maximize revenue in the situation you gave me to answer

Solve 2x + 6 - 10x = 30

Answers

2x+6-10x=30
2x - 10x = 24
  x=-3

Round 0.125 to the nearest tenth.

Answers

It would be .13. 
We round the 2 up since five is to the right either way it makes no different to the tenths place.
Answer: 0.13

After rounding off the given number 0.125 to the nearest tenth it becomes 0.1.

We know that,

When you round a number to a certain digit, you have to check the value of the digit before the place you want to round off to.

1. If the number you are rounding is followed by 5, 6, 7, 8, or 9, round the number up.

2. If the number you are rounding is followed by 0, 1, 2, 3, or 4, round the number down.

The given number is:

0.125

To round off this digit nearest tenth,

See the number at the hundredth place, which is 2.

And 2 < 5  

Therefore,

0.125 is rounded down to 0.1

So after rounding 0.125 number becomes 0.1.

Hence,

The rounded-off number nearest tenth is 0.1.

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Furry Pets pet store has 20 animals and 2/5 of them are puppies. Pets Galore pet store has 12 animals and 3/4 of them are puppies. Which store has more puppies?

Furry Pets
Pets Galore
Each store has the same number of puppies

Answers

Furry Pets answer is found by 20 x 2/5.

20 x 2/5

40/5

8

Furry Pets has 8 puppies.

Pets Galore has 12 animals and 3/4 puppies.

12 x 3/4

36/4

9

Pets Galore has 9 puppies.

8 is less than 9, so Pets Galore has more puppies.

The mathematics faculty at a college consists of 4 ​professors, 5 associate​ professors,  6 assistant​ professors, and 8 instructors. If one faculty member is randomly​ selected, find the probability of choosing a professor or an instructor.

Answers

There are a total of 4+5+6+8 = 23 faculty members. 

the probability of selecting a professor (4) or an instructor (8) is: 

(4+8)/ 23 => 12/23 => 0.54 or 54%
first you add everyone together.
8+6+5+4=23
since there are 5 associate professors and 8 instructors you add them together. 
4+8=12
you divide the number of professors and instructors by the number of everyone.
12/23=.52
you move the decimal over 1 place and there's your answer.
52%

An ordinary (fair) die is a cube with the numbers 

1

 through 

6

 on the sides (represented by painted spots). Imagine that such a die is rolled twice in succession and that the face values of the two rolls are added together. This sum is recorded as the outcome of a single trial of a random experiment.

Compute the probability of each of the following events:

Event 

A

: The sum is greater than 

9

.
Event 

B

: The sum is divisible by 

5

 or 

6

 (or both).

Answers


There are a few ways to look at this. If you wanted to look at all the events, you could draw a 6 x 6 grid and label the left side from 1 to 6 and the bottom from 1 to 6. The intersection of a row and a column would be a possible sum. You can check to see if the event you want to occur occurs on a cell by cell basis. Like if you wanted to see how many possibilities are there to get a sum of 12. We know there is only one way, that is to roll a 6 and a 6. Then you would shade the top right corner cell of the grid and check the other ones (for more complicated events). Then the probability is just the number of shaded cells divided by the total number of cells.

But, since you can probably just count the events, how many ways are there to roll any two numbers, if the order matters, there are 36 possibilities (6 x 6 grid). You could roll 4 then 6, 6 then 4, 5 then 5, 5 then 6, 6 then 5, and 6 then 6. There are 6 possibilities with a sum more than 9 and 36 total, so the probability of that one event is 6/36 or 1/6. Try out the last one ;)





Final answer:

The probability of rolling a sum greater than 9 (Event A) on two fair dice is 1/6, and the probability of rolling a sum divisible by 5 or 6 (Event B) is 1/3.

Explanation:

To compute the probability of Event A, where the sum is greater than 9, we first identify the possible combinations that yield a sum greater than 9: (4,6), (5,5), (5,6), (6,4), (6,5), and (6,6). Since there are 6 possible outcomes and 36 total possible outcomes when rolling two dice (6 for the first die × 6 for the second die), the probability is 6/36 or 1/6.

For Event B, we look for sums divisible by 5 or 6. These sums are 5, 6, 10, 12, 15, 18, and 20. The combinations yielding these sums are (1,4), (2,3), (2,6), (3,2), (3,6), (4,1), (4,6), (5,1), (5,5), (6,2), (6,3), (6,6). By counting these results, we have 12 outcomes that meet the Event B criteria out of 36, so the probability is 12/36 or 1/3.

The probability of Event A, the sum being greater than 9, is 1/6, and the probability of Event B, the sum being divisible by 5 or 6, is 1/3.

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The price of a notebook was
$3.90
yesterday. Today, the price fell to
$3.40
. Find the percentage decrease. Round your answer to the nearest tenth of a percent.

Answers

(3.90 - 3.40) / (3.90) = 0.50 / 3.90 = 0.128 x 100 = 12.8%

Final answer:

The percentage decrease in the price of the notebook from $3.90 to $3.40 is 12.8% when rounded to the nearest tenth of a percent.

Explanation:

To find the percentage decrease in the price of a notebook from $3.90 to $3.40, we use the formula for percentage change:

Percentage Change = [(Old Price - New Price) / Old Price] × 100%

Plugging in our values we get:

Percentage Decrease = [($3.90 - $3.40) / $3.90] × 100%

Percentage Decrease = [$0.50 / $3.90] × 100%

Percentage Decrease = 0.1282 × 100%

Percentage Decrease = 12.82%

When rounded to the nearest tenth, the percentage decrease is 12.8%.

A guy walks into a store and steals $100 from register, comes back and buys $70 worth of merchandise, pys for it with same $100 and gets $30 cash back. how much did store lose?

Answers

In order to know the answer for this one, let us analyze the whole problem.
Given that the store already lose $100 stolen by the guy, this guy also bought a merchandise worth 70$, and gets a change of $30. The merchandise was paid, but still, the store lost $100, and then an additional $30, for giving it back to the guy. So the total lost of the store would be $130. Hope this answer helps.

In a zoo the ratio of adults to children is 13 to 11. If there are 96 people in the zoo how many children are there?

Answers

13:11...added = 24

13/24(96) = 1248/24 = 52 <== adults
11/24(96) = 1056/24 = 44 <== children

In the week before and the week after a​ holiday, there were 10,000 total​ deaths, and 4958 of them occurred in the week before the holiday. a. Construct a 95​% confidence interval estimate of the proportion of deaths in the week before the holiday to the total deaths in the week before and the week after the holiday. b. Based on the​ result, does there appear to be any indication that people can temporarily postpone their death to survive the​ holiday?

Answers

Thank you for posting your question here at brainly. I hope the answer will help you. Feel free to ask more questions here.
Below is the solution:

p-hat = 5445 / 11000 = 0.495

For a 95% confidence interval, use z = 1.96

The confidence interval is then:

p-hat - z(√(p-hat)(1 - p-hat) / n) < p < p-hat + z(√(p-hat)(1 - p-hat) / n)

0.495 - (1.96)(√(0.495)(1 - 0.495) / 11000) < p < 0.495 + (1.96)(√(0.495)(1 - 0.495) / 11000)

0.486 < p < 0.504

write
23/25 as a percent

Answers

3 / 25 = x / 100 

23/25 = 0.92 = 92/100 

x = 92%
Convert the fraction to a decimal, then multiply by 100.
= 92%

rewrite as a logarithmic equation.
7^0=1

Answers

Convert the exponential equation to a logarithmic equation using the logarithm base ( 7 ) 7 of the right side ( 1 ) 1 equals the exponent ( 0 ) 0 . log 7 ( 1 ) = 0

I need help with a math problem.

Answers

11.2+4+3.4+7.3+(11.2-3.4)=
11.2+4+3.4+7.3+7.8=
33.7

your perimeter is 33.7 m
All you have to do is just add the sides, in order to find the perimeter.

4m + 3.4m + 7.3m + 11.2m = 25.9m
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