GRADE 8 UNIT 5 LESSON 5 OPEN UP RESOURCES
#3 A car is traveling on a small highway and is either going 55mph or 35mph, depending on the speed limits, until it reaches its destination 200 miles away. Letting x represent the amount of time in hours that the car is going 55mph, and y being the time in hours that the car is going 35mph, an equation describing the relationship is:
55x + 35y = 200
a. If the car spends 2.5 hours going 35mph on the trip, how long does it spend going 55mph?
b. If the car spends 3 hours going 55mph on the trip, how long does it spend going 35mph?
c. If the car spends no time going 35mph, how long would the trip take?

Answers

Answer 1

a. It spends 2.04 hours going 55 mph.

b. It will spend 1 hour going 35 mph.

c. The trip will take 3.64 hours.

Step-by-step explanation:

Given equation is;

55x + 35y = 200

Where

x represent the time when speed is 55 mph

y represent the time when speed is 35 mph

a. If the car spends 2.5 hours going 35mph on the trip, how long does it spend going 55mph?

Putting y=2.5 in given equation

[tex]55x+35(2.5)=200\\55x+87.5=200\\55x=200-87.5\\55x=112.5\\[/tex]

Dividing both sides by 55

[tex]\frac{55x}{55}=\frac{112.5}{55}\\x=2.04\ hours[/tex]

It spends 2.04 hours going 55 mph.

b. If the car spends 3 hours going 55mph on the trip, how long does it spend going 35mph?

Putting x=3 in given equation

[tex]55(3)+35y=200\\165+35y=200\\35y=200-165\\35y=35[/tex]

Dividing both sides by 35

[tex]\frac{35y}{35}=\frac{35}{35}\\y=1[/tex]

It will spend 1 hour going 35 mph.

c. If the car spends no time going 35mph, how long would the trip take?

Putting y=0 in given equation

[tex]55x+35(0) = 200 \\55x+0=200\\55x=200[/tex]

Dividing both sides by 55

[tex]\frac{55x}{55}=\frac{200}{55}\\x=3.636[/tex]

Rounding off

x = 3.64

The trip will take 3.64 hours

Keywords: linear equation, division

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Related Questions

usually 1/1000 of the headphones cannot pass the tests . if they found 5 headphones failing, how many headphones did the workers test?

Answers

Answer: 5000

Step-by-step explanation: 5/5000

Final answer:

The workers tested 5000 headphones.

Explanation:

To find out how many headphones the workers tested,



We can set up a proportion to solve the problem:



1/1000 = 5/x



Cross multiplying, we get:



x = 5 * 1000



x = 5000



Therefore, the workers tested 5000 headphones.

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a new stadium will seat 83,820. There will be 132 different sections. If each section seats same number of people, how many people will each section seat?

Answers

Answer:

635

Step-by-step explanation:

83,820 / 132 = 635

9+3x=6(3-x) what is the answer

Answers

Answer:

x = 1

Step-by-step explanation:

9 + 3x = 18 - 6x

3x + 6x = 18 - 9

9x = 9

X = 1

Answer:

Step-by-step explanation:

9+3x =6(3-x)

9+3x =6 ×3 - 6x

9+3x =18 -6x

Collect like terms

9-18= -6x-3x

-9 =-9x

Divide both sides by -9

-9/-9 =-9x/-9

Minus cancels minus and 9 divided by 9 is 1 on both sides

1 =x

x =1

For abc shown with vertices at A(-2,6),B(8,-2) and C(-8,-4), shown using coordinate geometry that the segment connecting the midpoint of sides Ac and BC is half the length of side AB.

Answers

Answer:

It is proved that AB = 2 × DE.

Step-by-step explanation:

The three vertices of triangle ABC are A(-2,6), B(8,-2) and C(-8,-4).

So, the mid point of AC (say D) has coordinates [tex](\frac{- 2 - 8}{2},\frac{6 - 4}{2}) = (-5,1)[/tex].

And the mid point of BC (say E) has coordinates [tex](\frac{8 - 8}{2}, \frac{- 2 - 4}{2}) = (0, - 3)[/tex].

Now, the length of DE will be [tex]\sqrt{(- 5 - 0)^{2} + (1 + 3)^{2}} = \sqrt{41}[/tex] units.

Again, the length of AB will be [tex]\sqrt{(- 2 - 8)^{2} + (6 + 2)^{2}} = 2\sqrt{41}[/tex] units.

So, it is proved that AB = 2 × DE. (Answer)

Solve for X (simple)

Answers

Answer:

156°

Step-by-step explanation:

This is simply angle on a straight and this angle is 180°

X + 24 = 180

Collect like terms

X = 180 — 24

X = 156°

WORTH 100 POINTS
A plane is racing a helicopter to a runway traveling 31 mph and it tends to burn 5 gallons of gas ever 3 minutes. Whilst the helicopter is traveling at a speed of 45 mph burning 7 gallons of gas every 5 minutes. They both started with the same amount of fuel (80 gallons) and both have the same amount to travel ( 640 miles) Who will make it first using the less amount of fuel?
Does this problem work?
If so what is the answer?
Show your work please

Answers

Answer:

The problem does not work.

Step-by-step explanation:

The plane with speed of 31 mph will cover 640 miles in [tex]\frac{640}{31} = 20.64[/tex] hours.

Now, it burns 5 gallons of gas every 3 minutes i.e. 0.05 hours.

So, it will burn in 20.64 hours [tex]\frac{5 \times 20.64}{0.05} = 2064[/tex] gallons.

Now, the helicopter with speed of 45 mph will cover 640 miles in [tex]\frac{640}{45} = 14.22[/tex] hours.

Now, it burns 7 gallons of gas every 5 minutes i.e. 0.083 hours.

So, it will burn in 14.22 hours [tex]\frac{7 \times 14.22}{0.083} = 1194.48[/tex] gallons.

But both of them starts with only 80 gallons of fuel.

Therefore, the problem does not work. (Answer)

2 Points
Which equation represents the slope-intercept form of the line below?
y-intercept = (0,2)
slope =
O A. y= 2x-}
O B. y=-x-2
O C. y=-_x+2
O D. y= 2x+

Answers

Answer:

the answer is C

Step-by-step explanation:

In the y intercept formula which is y=Mx+b the b in the formula represents the y intercept

Solve write or draw to explain Saul and Luisa each scored 167 points on computer games How many points did they score together

Answers

Answer:167 + 167 = 334

Step-by-step explanation:

I WILL GIVE BRAINLIEST
Solve for r

-13 = r/9 + 8

r=

Answers

Answer:

r= -45

Step-by-step explanation:

trust on this one

Answer:

-189

Step-by-step explanation:

what is the a, b, and r for y=3.6(1.25)^x

Answers

Answer:

a=3.6, v=1.25 and r=25%

Step-by-step explanation:

The given exponential function is

[tex]y = 3.6 {(1.25)}^{x} [/tex]

We compare to the form:

[tex]y = a{(b)}^{x} [/tex]

We have a=3.6, b=1.25

The r is the percentage of increase or decrease.

We realized there is a 25% increase because

[tex]y = 3.6 {(1 + 25\%)}^{x} [/tex]

Hence

[tex]r = 25\%[/tex]

A degree may seem like a very small unit but an error of one degree in measuring an angle may be very significant. For example, suppose a laser beam directed toward the visible center of the moon misses its assigned target by the amounts specified below. How far is it (in miles) from its assigned target in each case? (Use 234,000 miles as the distance from the surface of the earth to the surface of the moon.)
a: 1 degree
b: 30” (that’s 0 degree 0’ 30”)

Answers

To calculate the distance by which a laser beam misses its target on the moon due to an angular error, one can use the tangent function with the Earth-moon distance. For an error of 1 degree, it would miss by approximately 4,080 miles, and for an error of 30 arcseconds, by about 34 miles.

To find out how far a laser beam directed toward the center of the moon misses its target by 1 degree, we can use a simple trigonometric calculation. Since we are dealing with a right-angled triangle with the Earth-moon distance as one leg (the adjacent leg in this case), and we want to find the opposite leg which represents the distance on the moon's surface from the intended target, we can use the tangent function.

For an error of 1 degree:

Convert the degree to radians, because trigonometric functions in calculators usually use radians. There are π radians in 180 degrees, so 1 degree is (π/180) radians.

Use the formula distance = tangent of the angle in radians × Earth-moon distance. So distance = tan(1° × (π/180)) × 234,000 miles.

Calculate the tangent of 1° in radians (approximately 0.01745) and multiply by 234,000 miles.

The result is approximately 4,080 miles.

For an error of 30 arcseconds (30″):

There are 60 arcseconds in 1 arcminute and 60 arcminutes in 1 degree, hence 30 arcseconds is 30/60/60 degrees, which equals 1/120 degrees.

Convert 1/120 degrees to radians similarly as before.

Use the same tangent formula: distance = tan((1/120)° × (π/180)) × 234,000 miles.

Calculate the tangent of (1/120)° in radians (approximately 0.000145444) and multiply by 234,000 miles.

This results in approximately 34 miles from the assigned target.

7.8 dividend by 0.03

Answers

Answer:

its 26

Step-by-step explanation:

give me brainly

Write an equation that relates y, and the dependent quantity, to x, the independent quantity, if the slope is 2/3 and the y-intercept is -7.

Answers

Answer:

Step-by-step explanation:

y = mx + b....in this form, the slope will be in the m position and the y int will be in the b position

so ur equation is : y = 2/3x - 7

what is the range of the function f(x)=12-3x for the domain {-4,-2,0,2,4}
A) 24,18,12,6,20
B) 6,12,18,24,30
C) -12,-6,0,6,12
D) 0,6,12,18,24​

Answers

Answer:

D) 0,6,12,18,24

Step-by-step explanation:

What is the solution 4x+6<18

Answers

Answer:

x < 3

Step-by-step explanation:

4x +6 < 18

add and subtract 6 from both sides

4x + 6 - 6 < 18 -6

4x < 12

x< 12/4

X < 3

Answer:

x < 3

Step-by-step explanation:

I took the test its, the right answer, trust me.

Josie's dog weighs 122 pounds. This is about 7 times as much as Len's dog weighs. About how much does Len's dog weigh? Select the numbers that correctly complete the sentence. Len's dog weighs between pounds.

Answers

Divide the weight of Josies dog by 7:

122 / 7 = 17.43

It weighs between 17 and 18 pounds.

Final answer:

Len's dog weighs about 17 pounds, calculated by dividing Josie's dog's weight (122 pounds) by 7 since her dog is approximately 7 times heavier than Len's.

Explanation:

Josie's dog weighs 122 pounds, which is about 7 times as much as Len's dog weighs. To find the weight of Len's dog, we need to divide the weight of Josie's dog by 7. Here's the calculation:

122 pounds by 7 = approximately 17.43 pounds

Therefore, Len's dog weighs about 17 pounds. This is a unit of weight that makes sense for the size of a dog. We choose pounds because ounces would be too small and tons would be too large to represent the weight of a large dog accurately. Thus, using pounds is appropriate to express the weight of a dog, such as Len's dog in this case.

3 is 50% of what number

Answers

If you double 50%, you get 100%. If you double 3 you will get 6. 3 is 50% of 6.

What is (8×^2+4×+6)(6×^2-5×+6)

Answers

Answer:

1

Step-by-step explanation:

I think it's 1 because I never did this question before.

2×1 1/2 -1 1/2×1 1/2

Answers

Answer:

3/4

Step-by-step explanation:

Answer:

3/4

Step-by-step explanation:

how to solve 6x-9 = 3x + 4

Answers

Subtract 3x on both sides: 6x-3x-9=3x-3x+4 which is 3x-9=4

Add 9 to both sides: 3x+9-9=4+9 which is 3x=13

Divide both sides by 3 to get x=13/3 or 4 1/3

Hope this helped!

Answer:

 x = 13/3 = 4.333

Step-by-step explanation:

   6*x-9-(3*x+4)=0  

Step  1  :

Solving a Single Variable Equation :

  Solve  :    3x-13 = 0  

Add  13  to both sides of the equation :  

                     3x = 13

Divide both sides of the equation by 3:

                    x = 13/3 = 4.333

If x varies inversely as y, and x = 3 when y= 8, find y when x=4

Answers

The value of y is 6 when x is 4

Step-by-step explanation:

If x varies inversely as y, then

x = [tex]\frac{k}{y}[/tex] , where k is the constant of variationxy = k, you can find k by using the initial values of x and y[tex]\frac{x_{1}}{x_{2}}=\frac{y_{2}}{y_{1}}[/tex]

∵ x varies inversely as y

∴ x = [tex]\frac{k}{y}[/tex]

∵ When x = 3, y = 8

- Substitute these values in the equation to find k

∴ 3 = [tex]\frac{k}{8}[/tex]

- Multiply both sides by 8

24 = k

∴ The equation of variation is x = [tex]\frac{24}{y}[/tex]

x = 4

- Substitute the value of x in the equation to find y

∴ 4 = [tex]\frac{24}{y}[/tex]

- Multiply both sides by y

∴ 4y = 24

- Divide both sides by 4

y = 6

The value of y is 6 when x is 4

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ANSWER THIS FAST
BRANLIEST IS ON THE LINE in

Answers

Answer:

Option A.) is correct  [tex]\triangle XYZ \sim \triangle WVZ[/tex]  by AA similarity. There are two angles that are congruent given by [tex]\angle ZXY = \angle ZWV \hspace{0.2cm} and\hspace{0.2cm} \angle ZYX = \angle ZVW[/tex].

This is because both pairs represent alternate interior angles formed by lines intersecting two parallel lines.

Step-by-step explanation:

From the given figure we can say that

i) Option A.) is correct  [tex]\triangle XYZ \sim \triangle WVZ[/tex]  by AA similarity. There are two angles that are congruent given by [tex]\angle ZXY = \angle ZWV \hspace{0.2cm} and\hspace{0.2cm} \angle ZYX = \angle ZVW[/tex].

This is because both pairs represent alternate interior angles formed by lines intersecting two parallel lines.

How do you evaluate 2x3x5

Answers

Answer:

Step-by-step explanation:

Answer:I think it's 30

Step-by-step explanation:

Because 2x3=6 and 6x5= 30

What is 129 multiply by 75

Answers

129 multiplied by 75 equals 9,675.
The product is 9,675

The graph below is a parabola, so it can be represented by a quadratic function. Which of the following quadratic functions could represent this graph.
y=-(x-2)^2-4
y=(x-2)^2+4
y=-(x+2)^2+4
y=-(x-2)^2+4

Answers

Answer:

y=(x-2)^2+4

Step-by-step explanation:

The quadratic function that represents the parabola is y = - (x - 4)² + 4.

What is a quadratic equaton?

A quadratic equation is an algebraic expression in the form of variables and constants.

A quadratic equation has two roots as its degree is two.

From the graph of the function, the parabola intersects the x-axis

at 0 and 4, and we also know when a parabola opens downwards the equation is negative.

So, The required equation is y = - (x - 0)(x - 4).

y = - (x² - 4x).

y = - {x² - 4x + 4 - 4}.

y = - { (x - 2)² - 4}.

y = - (x - 4)² + 4.

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Given that S is the centroid of triangle MNO, find SQ.

Answers

Answer:

|SQ|=5

Step-by-step explanation:

If S is the median, then OP is a median of triangle OMN.

This implies that:

|MP|=|NP|

[tex]3x-4=x+4[/tex]

We group like terms and solve for x.

[tex]3x-x=4+4[/tex]

[tex]\implies 2x=8[/tex]

[tex]\implies x=4[/tex]

Now we know that: MN:SQ=2:1

But MN=2x+2

This implies that:

2x+2:SQ=2:1

Put x=4

2(4)+2:SQ=2:1

10:SQ=2:1

Therefore |SQ|=5

Find A n B if A = {4, 7, 10, 13, 17) and B = {3, 5, 7, 9)

Answers

Answer:

look at the picture ahown

Write a system of equations to describe the situation below. Sparkles the Clown makes balloon animals for children at birthday parties. At Jenny’s party, she made 2 balloon poodles and 2 balloon giraffes, which used a total of 12 balloons. For Roger’s party, she used 27 balloons to make 4 balloon poodles and 5 balloon giraffes. How many balloons does each animal require?

Answers

Final answer:

A system of equations to represent the situation with Sparkles the Clown is: 2p + 2g = 12 for Jenny's party and 4p + 5g = 27 for Roger's party. We can use substitution or elimination methods to solve for 'p' and 'g' to determine the number of balloons needed for each animal.

Explanation:

To write a system of equations based on the given situation with Sparkles the Clown, we will let 'p' represent the number of balloons needed for a poodle and 'g' represent the number of balloons needed for a giraffe. From Jenny's party, we know that 2 poodles plus 2 giraffes used a total of 12 balloons. From Roger’s party, we learn that 4 poodles plus 5 giraffes used a total of 27 balloons. Therefore, our system of equations to represent this situation is:

2p + 2g = 12 (Jenny's party)4p + 5g = 27 (Roger's party)

To solve this system of equations, we could use methods such as substitution or elimination to find the values of 'p' and 'g' which would tell us how many balloons are required for each balloon animal.

Final answer:

To find out how many balloons are required for each balloon animal, we set up a system of equations with p representing the number of balloons for a poodle, and g for a giraffe. The system is based on the balloon usage at two parties, resulting in the equations 2p + 2g = 12 and 4p + 5g = 27.

Explanation:

To solve the problem of how many balloons Sparkles the Clown needs for each type of balloon animal, we need to set up a system of linear equations based on the given information. We will let p represent the number of balloons needed for a poodle, and g represent the number for a giraffe.

From Jenny's party, we have the first equation:

2p + 2g = 12

From Roger's party, we have the second equation:

4p + 5g = 27

Now, we have established our system of equations:

1) 2p + 2g = 12

2) 4p + 5g = 27

Solving this system will give us the number of balloons needed to make each type of balloon animal.

MAPS On a map, Wilmington Street, Beech Drive, and Ash Grove Lane appear to all be parallel. The on

ilmington to Ash Grove along Kendall is 820 feet and along Magnolia, 660 feet. If the distance between Beech and

ove along Magnolia is 280 feet, what is the distance between the two streets along Kendall?

Answers

The distance between the two streets along Kendall is 347.9 feet.

Solution:

The image of the problem is attached below.

Distance between Wilmington to Ash Grove along Kendall = 820 feet

Distance between Wilmington to Ash Grove along Magnolia = 660 feet

Distance between Beech and  Ash Grove along Magnolia = 280 feet

Distance between Wilmington to Beech along Magnolia

                                       = 660 feet – 280 feet

                                       = 380 feet

Let us x be the distance between Wilmington to Beech along Kendall and

820 – x be the distance between Beech and  Ash Grove along Kendall.

The given streets are parallel.

By proportionality theorem, parallel lines cut by a transversal are in proportion.

[tex]$\Rightarrow\frac{380}{280} =\frac{x}{820-x}[/tex]

Do cross multiplication.

[tex]$\Rightarrow{380}({820-x}) =280x[/tex]

[tex]$\Rightarrow 311600-380x =280x[/tex]

[tex]$\Rightarrow 311600 =280x+380x[/tex]

[tex]$\Rightarrow 311600 =660x[/tex]

[tex]$\Rightarrow x=472.1[/tex]

Distance between Beech and  Ash Grove along Kendall          

                                    = 820 – x  

                                    = 820 – 472.1

                                    = 347.9

Hence the distance between the two streets along Kendall is 347.9 feet.

Final answer:

By analyzing the given distances along two parallel paths and using proportional reasoning, it is determined that the distance between Beech Drive and Ash Grove Lane along Kendall is approximately 547.33 feet.

Explanation:

Since Wilmington Street, Beech Drive, and Ash Grove Lane are parallel, and given the distances along Kendall and Magnolia, we can deduce the relationships between these distances to find the desired measurement. Utilizing the ratio of distances along Magnolia, we can apply the same ratio to the distances along Kendall.

We know that the total distance along Magnolia (660 feet) minus the distance between Beech and Ash Grove (280 feet) gives the distance between Wilmington and Beech along Magnolia, which is 380 feet. Assuming the distance distribution is proportional along Kendall, the distance between Beech and Ash Grove along Kendall would be given by:

(280 feet / 660 feet) * 820 feet = (2/3) * 820 feet = 547.33 feet.

Therefore, the distance between Beech Drive and Ash Grove Lane along Kendall is approximately 547.33 feet.

Find the distance (D) Round your answer the nearest tenth.PLEASE HELP!!

Answers

Using the distance formula
The answer is square root 29

Or 5.4
Final answer:

The distance (D) is 10 cm.

Explanation:

To find the distance (D), we can use the formula D = do + di, where do is the actual distance and di is the apparent image distance.

In the given information, it states that 2do must be less than 20 cm, so we can set do = 10 cm.

Therefore, the distance (D) is 10 cm.

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When Akiko measured a rose, its height was 5.8 in. After 10 weeks, the height was 1 1/3 times the original height. What was the height of the rose after 10 weeks? In May, Xiang sold 15 used cars. For these 15 cars, the range of the selling price was $15,000 and the lowest selling price was $4,500. In June, Xiang sold 10 used cars. For these 10 cars, the range of the selling prices was $16,500 and the lowest selling price was $6,100. What was the range of the selling prices of the 25 used cars sold by Xiang in May and June?A. $15,600B. $15,750C. $16,820D. $18,100E. $19,200 Tardigrades, also called water bears, are microscopic segmented animals with eight legs. They are normally about 70 percent body water, but they can survive extreme dehydration (to just a few percent body water) for up to 10 years! After a decade you can add water and the tardigrades will start swimming around. You enter a lab and your new boss gives you five dehydrated tardigrades and asks you to demonstrate that the tardigrades are alive in their dehydrated state. How would you demonstrate this? a. Record their movement, because movement is characteristic of all life. b. Record their temperature, because all living organisms maintain body temperatures different from their environment. c. Record their energy use, because all living organisms acquire and use energy. d. None of the options listed demonstrate that the dehydrated tardigrades are alive A lithium flame has a characteristic red color due to emissions of wavelength 671 nm. What is the mass equivalence of 1 mol of photons of this wavelength (1 J = 1 kgm/s)? Lillian earns $44 in 4 hours. At this rate, how many dollars will she earnin 30 hours?1 of 38 QUESTIONS$440$300O $330$110SUBMIT If changing market conditions cause a company earning $7,000,000 in 2018 to project a loss of 4% of its profit in each of the next 5 years, what profit does it project in 2023? (Round your answer to the nearest dollar.) The main idea of the passage is thatChoose 1 answer:delivering food in a restaurant is more demanding than many people realize.cognitive psychology can improve the efficiency of a variety of businesses.alphanumeric codes can often improve the performance of restaurant servers.the isolation effect only affects memory in tasks with high-load conditions. Which type of account do businesses use to record their financial transactions?A __________account, also called a T-shaped account, is a format in which businesses record their financial transactions. what gas is used by plants during photosynthesis, where does it come from, and where does it enter the plant? identify this coefficient 8x Have advances in agriculture improved the human condition, or have the benefits of the Green Revolution been limited to a few geographic regions? if f(x) = 5x - 7, what is f(3)?A. 22B. 8c. 2D. 1 11) What is the important outcome of meiosis I? Exocytosis is a type of cellular transport that allows materials to move across the plasma membrane of a cell. Which of the statements describe properties of exocytosis? a. Exocytosis is the primary method of transporting large molecules out of the cell. b. Exocytosis is the primary method of transporting large molecules into the cell c. Exocytosis uses transport vesicles to export materials from the cell d. Exocytosis uses membrane channel proteins to import materials into the cell. e. Exocytosis uses transport vesicles to import materials into the cell. You are offered an investment that will make three $5,000 payments. The first payment will occur four years from today. The second will occur in five years, and the third will follow in six years. If you can earn 12 percent, what is the future value of the cash flows? What is the most this investment is worth today? A physiological or psychological dependence on a drug is?A. illegal DrugsB. AddictionC. OverdoseD. Substance Abuse The process by which the Supreme Court makes the protections of the Bill of Rights applicable to the states is ______. The House Committee on Un-American Activities was known for seeking out communists in what industry?a)The film industryb)The oil industryc)The car industryd) the steel industry How did the Immigration Act of 1924 change immigration rates in the UnitedStates? Given two dependent random samples with the following results: Population 15876777062766776 Population 26469836066846081 Can it be concluded, from this data, that there is a significant difference between the two population means? Let d=(Population 1 entry)(Population 2 entry). Use a significance level of =0.01 for the test. Assume that both populations are normally distributed.