A supermarket is redesigning it’s checkout lanes. Design A has a sample size of 50, sample mean of 4.1 minutes, and sample standard deviation of 2.2 minutes. Design B has a sample size of 50, sample mean of 3.5 minutes, and sample standard deviation of 1.5 minutes. At the 0.05 level of significance, determine if their is evidence that the checkout times of the two systems differ.

Answers

Answer 1

Answer:

The calculated value t = 1.57736 < 1.9845 at 5 % level of significance

Null hypothesis is accepted at 5 % level of significance

There is no significance difference between Design A and Design B

Step-by-step explanation:

Given  sample size of design A

                                            n₁ = 50

sample mean of design A x⁻₁ = 4.1 minutes

Sample standard deviation S₁ = 2.2 minutes

Given  sample size of design B

                                            n₂ = 50

sample mean of design A x⁻₂ = 3.5 minutes

Sample standard deviation S₂ = 1.5 minutes

Null Hypothesis : H₀ : There is no significance difference between Design A and Design B

Alternative Hypothesis : H₁:There is  significance difference between Design A and Design B

Level of significance ∝ = 0.05

Test statistic

[tex]t = \frac{x^{-} _{1}- x^{-} _{2} }{\sqrt{S^{2} (\frac{1}{n_{1} }+\frac{1}{n_{2} }) } }[/tex]

where

[tex]S^{2} = \frac{n_{1} S_{1} ^{2} +n_{2} S^2_{2} }{n_{1} +n_{2} -2}[/tex]

[tex]S^{2} = \frac{50 (2.2)^{2} +50(1.5)^2}{50+50-2}[/tex]

On calculation , we get

S² = 3.6173

Test statistic

                   [tex]t = \frac{4.1-3.5}{\sqrt{3.617(\frac{1}{50} +\frac{1}{50} }) }[/tex]

On calculation , we get

   t = 1.57736

Degrees of freedom

ν = n₁ + n₂ -2 = 50 +50 -2 =98

t₀.₀₂₅ ,₉₈ = 1.9845

The calculated value t = 1.57736 < 1.9845 at 5 % level of significance

null hypothesis is accepted


Related Questions

Please help. I’ll mark you as brainliest if correct!

Answers

Answer:

a= -3/8

b= 1/8

Step-by-step explanation:

To remove i from the denominator, we need to multiply the numerator and denominator by -i

[tex]\frac{(-1-3i)(-i)}{8i(-i)}[/tex]

This simplifies to

[tex]\frac{i+3i^{2} }{-8i^{2} }[/tex]

This further simplifies to

[tex]\frac{i-3}{8}[/tex]

This can be rewritten as

[tex]-\frac{3}{8} +\frac{1}{8} i[/tex]

a= -3/8

b= 1/8

Answer:

[tex] a = - \frac{3}{8} \\ \\ b = \frac{1}{8} [/tex]

Step-by-step explanation:

[tex] \frac{ - 1 - 3i}{8i} \\ \\ = \frac{ - 1 - 3i}{8i} \times \frac{i}{i} \\ \\ = \frac{( - 1 - 3i)i}{8i \times i} \\ \\ = \frac{ -1 \times i - 3 {i}^{2} }{8 {i}^{2} } \\ \\ = \frac{ - i - 3 ( - 1)}{8 ( - 1) } \\ \\ = \frac{ - i + 3}{ - 8} \\ \\ = \frac{ i - 3}{ 8} \\ \\ = \frac{ - 3 + i}{ 8} \\ \\ = \frac{ - 3}{8} + \frac{i}{8} \\ \\ \purple{ \bold{ = - \frac{3}{8} + \frac{1}{8} i}} \\ equating \: it \: with \: a + bi \\ \\ a = - \frac{3}{8} \\ \\ b = \frac{1}{8} \\ [/tex]

An amount was invested at % r per quarter. What value of rwill ensure that accumulated amount at the end of one year is 1.5 times more than amount invested? Correct to 2 decimal places

Answers

Answer:

  42.67%

Step-by-step explanation:

The annual growth factor for interest at annual rate r compounded quarterly is ...

  (1 +r/4)^4

You want that value to be 1.5:

  1.5 = (1 +r/4)^4

  1.5^(1/4) = 1 +r/4

  (1.5^(1/4) -1) = r/4

  4(1.5^(1/4) -1) = r ≈ 0.426728

The rate r must be about 42.67%.

_____

Comment on the wording

We interpreted the problem to mean the end-of-year amount is 1.5 times the beginning-of-year amount. That is, it is "1.5 times the amount invested."

The word "more" is typically used when addition is involved. For example, "25% more" means 25% of the original is added to the original. We occasionally see "more" where "x times more" is intended to mean "x times", rather than "x times the amount, added to the original amount."

NEED HELP ASAP
Solve the equation or inequality for the unknown number. Show your work.


Answers

Answer:

5

Step-by-step explanation:

3(14+x) = 57

42 +3x = 57

3x = 15

x = 5

PLEASE ANSWER THIS , I WILL MAKE U BRAINLIEST IF RIGHT

Answers

Answer:

hope this helps you

~I will mark as BRANLIEST and give you 55 points if you answer correctly.

Answers

Answer:

The lines would intersect at: (6, -4)

Step-by-step explanation:

I graphed both lines.

Answer:

(4,-2)

Step-by-step explanation:

The equation for the graphed line is [tex]y=\frac{1}{2} x-4[/tex] as it has a slope of [tex]\frac{1}{2}[/tex] and a y-intercept of -4.

Now that we have the two equations, we can set them equal to each other to find the x-value at which they intersect

[tex]\frac{1}{2} x-4=-x+2[/tex]

First, we can add 4 to each side

[tex]\frac{1}{2} x=-x+6[/tex]

Then we can add x to each side

[tex]\frac{3}{2} x=6[/tex]

Now we need to divide both side by [tex]\frac{3}{2}[/tex], which is the same thing as multiplying by [tex]\frac{2}{3}[/tex]

[tex]x=6*\frac{2}{3} \\\\x=\frac{12}{3} \\\\x=4[/tex]

Now that we have the x-value, we can plug it into one of the equations to see the y-value for where they intersect.

[tex]y=-x+2\\\\y=-(4)+2\\\\y=-2[/tex]

This means that the coordinates for the intersection of these two lines would be [tex](4,-2)[/tex]

Q 4.6: In a survey of 1,000 adults living in a big city, 540 participants said that they prefer to get news from the Internet, 330 prefer to watch news on TV, and 130 are rarely interested in the current news. We want to test if the proportion of people getting the news from the Internet is more than 50%. By generating the randomization distribution, we find that the p-value is 0.0057. Choose the correct statement interpreting the p-value.

Answers

Answer:

Option E is correct.

Step-by-step explanation:

In a survey of 1,000 adults living in a big city, 540 participants said that they prefer to get news from the Internet, 330 prefer to watch news on TV, and 130 are rarely interested in the current news. We want to test if the proportion of people getting the news from the Internet is more than 50%. By generating the randomization distribution, we find that the p-value is 0.0057. Choose the correct statement interpreting the p-value.

A.If the proportion of people getting the news from the Internet is not equal to 0.5 then there is a 0.0057 chance of seeing the sample proportion as extreme as the survey results.

B. If the proportion of people getting the news from the Internet is not equal to 0.54 then there is a 0.0057 chance of seeing the sample proportion as extreme as the survey results.

C. If the proportion of people getting the news from the Internet is equal to 0.54 then there is a 0.0057 chance of seeing the sample proportion less extreme compared to the survey results. р

D. If the proportion of people getting the news from the Internet is equal to 0.54 then there is a 0.0057 chance of seeing the sample proportion as extreme as the survey results.

E. If the proportion of people getting the news from the Internet is equal to 0.5 then there is a 0.0057 chance of seeing the sample proportion as extreme as the survey results.

The correct interpretation of P value will be:

if the proportion of people getting the news from internet is equal to 0.5 then there is a 0.0057 chance of seeing the sample proportion as extreme as survey results.

Option E is correct.

Which is the graph of f(x) = 2(3)^x?

Answers

Answer: The graph is:

Show that an implicit solution of 2x sin2(y) dx − (x2 + 10) cos(y) dy = 0 is given by ln(x2 + 10) + csc(y) = C. Differentiating ln(x2 + 10) + csc(y) = C we get 2x x2 + 10 + dy dx = 0 or 2x sin2(y) dx + dy = 0. Find the constant solutions, if any, that were lost in the solution of the differential equation. (Let k represent an arbitrary integer.)

Answers

Answer:

Step-by-step explanation:

[tex]2xsin(2y)dx-(x^2+10) cosy dy =0\\\\\frac{2x}{x^2 + 10}dx= \frac{cosy}{sin(2y)}[/tex]

Take integration both side (apply substitution for the left hand side, apply sin(2y) = 2 sin(y) cos(y) for the right hand side) you will have the condition.

Problem solved

Oliver had $43 on the day before his birthday. After he received some money for his birthday, he had $68. Write an equation to find how much money Oliver received for his birthday.

Answers

Answer:

$25

Step-by-step explanation

If oliver had $43 before his birthday he was given (+) an amount of money, in order to find out  how much money was given you need to reverse the equation (-) $68-$43= $25

Please help. I’ll mark you as brainliest if correct!!!!

Answers

Answer:

a= 2/5

b= -3/5

Step-by-step explanation:

We need to multiply the numerator and denominator by -i (conjugate) to cancel out i in the denominator

[tex]\frac{(3+2i)(-i)}{5i(-i)}[/tex]

This simplifies to:

[tex]\frac{-3i+-2i^{2} }{-5i^{2} }[/tex]

This further simplifies to:

[tex]\frac{-3i +2}{5}[/tex]

Can be rewritten as:

[tex]\frac{2}{5} +-\frac{3}{5} i[/tex]

a = 2/5

b = -3/5

Arlinda says there is a linear relationship between the price (p) of 500ml soft drink and the number sold (x). The formula is x = ap + b where a and b are constants. At N$20 she sells 1500 of the 500ml soft drinks but the quantity sold falls by 200 of the 500ml soft drinks when she increases the price by 50%. At what price will 600 of the 500ml energy drinks be sold?

Answers

Answer: 600 of the 500ml energy drinks be sold be sold at $45

Step-by-step explanation:

The linear relationship between the price (p) of 500ml soft drink and the number sold (x) is expressed as

x = ap + b

At N$20 she sells 1500 of the 500ml soft drinks. This means that the first equation would be

1500 = 20a + b - - - - - - - - -1

the quantity sold falls by 200 of the 500ml soft drinks when she increases the price by 50%. This means that the new quantity sold is 1500 - 200 = 1300

The price at which they were sold is

20 + (50/100 × 20) = $30

The second equation would be

1300 = 30a + b - - - - - - - - -2

Subtracting equation 2 from equation 1, it becomes

200 = - 10a

a = 200/- 10 = - 20

Substituting a = - 20 into equation 2, it becomes

1300 = 10 × - 20 + b

1300 = - 200 + b

b = 1300 + 200 = 1500

The linear relationship becomes

x = - 20p + 1500

If x = 600, then

600 = - 20p + 1500

- 20p = 600 - 1500 = - 900

p = - 900/ - 20

p = $45

Leroy is 22 years old. His car averages 31 miles
per gallon. His car payments are $165.32 per
month, and he has 36 more payments to
make. How old will he be when he pays off his
car?

Answers

Answer:

he will be 25

Step-by-step explanation:

36 monthly payments left/12 payments a year = 3 years. 22 + 3 = 25

A rhombus is a quadrilateral with four congruent sides. The perimeter of rhombus WXYZ is less than 32 inches. Which inequality can be used to find all possible side lengths, s, for rhombus WXYZ? s squared greater-than 32 s squared less-than 32 4 s less-than 32 4 s greater-than 32

Answers

Answer:

4s< 32

Step-by-step explanation:

Congruent sides mean they are all the same length

Let the length be s

Perimeter means add the sides

s+s+s+s < 32

4s< 32

Answer:

4s>32

Step-by-step explanation:

your welcome dears

A tank contains 24 gallons of water when all of a sudden the water begins draining at a constant rate of 2 gallons per hour. Let t represent the number of hours since the water began draining and let v represent the volume of water in the tank.

Required:
a. Write a formula that expresses v in terms of t.
b. As t increases from 3 to 6, v varies from _________ to _________

Answers

Answer:

a) [tex]V(t) = 24 - 2t[/tex]

b) As t increases from 3 to 6, v varies from 18 gallons to 12 gallons.

Step-by-step explanation:

The volume of the tank in terms of the time can be described by the following equation:

[tex]V(t) = V(0) - at[/tex]

In which V(0) is the initial volume and a is the hourly decrease rate.

a. Write a formula that expresses v in terms of t.

The tank initially contains 24 gallons of water, which means that [tex]V(0) = 24[/tex]

Drains at a constant rate of 2 gallons per hour, so [tex]a = 2[/tex]

Then

[tex]V(t) = V(0) - at[/tex]

[tex]V(t) = 24 - 2t[/tex]

b. As t increases from 3 to 6, v varies from _________ to _________

[tex]V(t) = 24 - 2t[/tex]

[tex]V(3) = 24 - 2*3 = 18[/tex]

[tex]V(6) = 24 - 2*6 = 12[/tex]

So as t increases from 3 to 6, v varies from 18 gallons to 12 gallons.

NEED THE ANSWER PLS TIMER
Angela was given this expression to simplify. Negative 2 (2 x + 1) minus 3 (x + 3). Consider her steps in simplifying: 1. Negative 2 (2 x) + (negative 2) (1) + negative 3 (x) + (negative 3) (3). 2. Negative 4 x + negative 2 + negative 3 x + negative 9. 3. Negative 7 x minus 11.

Which statements are true about the steps Angela used? Check all that apply.

In step 1, she distributed –2 through the parentheses.

In step 1, she distributed 3 through the parentheses.

In step 2, she added the factor to the value inside the parentheses.

In step 2, she multiplied the factor to the value inside the parentheses.

In step 3, she combined like terms.

Answers

9514 1404 393

Answer:

In step 1, she distributed –2 through the parentheses.In step 1, she distributed 3 through the parentheses.In step 2, she multiplied the factor to the value inside the parentheses.In step 3, she combined like terms.

Step-by-step explanation:

In step 1 Angela used the distributive property to eliminate both sets of parentheses. In step 2, she found each of the products she indicated in step 1. In step 3, she combined like terms.

Answer:

the answer is a,d,e

Step-by-step explanation:

Find the volume of the cone.
Please help

Answers

Answer:1232m^3

Step-by-step explanation:

1/3 *22/7*7^2*24

1232m^3

Classify the following triangle. Check all that apply.
35°
10.1
7
102"
6
O A. Isosceles
O B. Equilateral
O c. Obtuse
O D. Right
O E. Scalene
F. Acute

Answers

Answer: obtuse and scalene

Step-by-step explanation:

Answer:

Obtuse And Scalene

Step-by-step explanation:

trust me!

What’s the correct answer for this?

Answers

Answer:

C

Step-by-step explanation:

Measure of Arc FED = 51+79

= 130°

Since the measures of arcs and angles are the same

Hence

<FED = 130°

Select all fractions that are equal to 3/4

Answers

3/4, 6/8, 9/12, 12/16 , 15/20, 18/24, 21/28, 24/32 , 27/36, 30/40, 33/44, 36/48 , 39/52, 42/56, 45/60, 48/64 , 51/68, 54/72, 57/76, 60/80, ect..

I hope this is what you are looking for :)

Entrance to a prestigious MBA program in India is determined by a national test where only the top 10% of the examinees are admitted to the program. Suppose it is known that the scores on this test are normally distributed with a mean of 420 and a standard deviation of 80. Parul Monga is trying desperately to get into this program. What is the minimum score that she must earn to get admitted?

Answers

Answer:

The minimum score that she must earn to get admitted is 523.

Step-by-step explanation:

As the scores are normally distributed, we can calculate the probability using the z-score.

The distribution has a mean of 420 and a standard deviation of 80.

We have to calculate the z-score z* that satisfies:

[tex]P(z>z^*)=0.1[/tex]

This happens for z*=1.28155.

Then, we can calculate the score as:

[tex]X=\mu+z\cdot\sigma=420+1.28155\cdot 80=420+102.524=522.524[/tex]

what is the midpoint of the segment shown below?
(1, 2) (1,-5)

A. (1, -3/2)
B. (2, -3/2)
C. (2, -3)
D. (1, -3)

Answers

Answer:

The answer is A (1,-3/2)

Step-by-step explanation:

Add both x coordinates, divide by 2

Add both y coordinates, divide by 2

The freezer contains vanilla and chocolate ice cream. Chocolate ice cream contains 12 servings less than vanilla. How many servings of vanilla ice cream are in the freezer if there are a total of 40 servings of ice cream? (Solve by building an equation)

Answers

Answer:

26 servings

Step-by-step explanation:

Let the number of servings of vanilla ice cream be x.

Number of servings of chocolate ice cream

= x -12

(since it has 12 servings less than vanilla)

Total servings= servings of chocolate+ vanilla

x + x-12= 40

2x -12 =40 (simplify)

2x= 40 +12 (+12 on both sides)

2x= 52 (simplify)

x= 52 ÷2

x= 26

Therefore, there are 26 servings of vanilla ice cream in the freezer.

Solve for m:
-3(1 – 5m) = — 38 + 8m

Answers

Answer:

m = - 5

Step-by-step Explanation:

[tex]-3(1-5m)=-38+8m \\ \\ - 3 + 15m = - 38 + 8m \\ \\ 15m - 8m = 3 - 38 \\ \\ 7m = - 35 \\ \\ m = \frac{ - 35}{7} \\ \\ \huge \purple{ \boxed{m = - 5}}[/tex]

Answer:

-5

Step-by-step explanation:

The equation 4x-45=y is used to find your profit y in dollars from buying $45 of supplies and washing cars for $4 what does the x stand for

Answers

33333333333333336666666666

If f(x)=x³-2x², which expression equivalent to f(i)?

Answers

Answer:

f(x) = x³ - 2x²

=>

f(i) = i³- 2i²

Hope this helps!

:)

Sick computers: Let V be the event that a computer contains a virus, and let W be the event that a computer contains a worm. Suppose
P(V) = 0.47, P(W) = 0.37, P(Vand W) = 0.01
(a) Find the probability that the computer contains either a virus or a worm or both.
(b) Find the probability that the computer does not contain a worm
Part 1 of 2
(a) Find the probability that the computer contains either a virus or a worm or both.
The probability that the computer contains either a virus or a worm or both is
Х
5
Part 2 of 2
(b) Find the probability that the computer does not contain a worm
The probability that the computer does not contain a worm is
Х

Answers

Answer:

0.83

0.63

Step-by-step explanation:

P(V or W) = P(V) + P(W) − P(V and W)

P(V or W) = 0.47 + 0.37 − 0.01

P(V or W) = 0.83

P(not W) = 1 − P(W)

P(not W) = 1 − 0.37

P(not W) = 0.63

a. the probability that the computer contains either a virus or a worm or both is 0.83

b. The probability that the computer does not contain a worm is 0.63.

Calculation:

(a)

The probability is

P(V or W) = P(V) + P(W) − P(V and W)

P(V or W) = 0.47 + 0.37 − 0.01

P(V or W) = 0.83

(b) The probability is

P(not W) = 1 − P(W)

P(not W) = 1 − 0.37

P(not W) = 0.63

Learn more about the probability here: https://brainly.com/question/16096170

Omar has three t shirts: one red, one green and one yellow. He has two pairs of shorts one black and red.
-How many different outfits can Omar put together?
-What is the probability of Omar’s outfits including a red T-shirt or red shorts?

Answers

Answer:

Omar can put together 6 outfits.

66.67% probability of Omar’s outfits including a red T-shirt or red shorts

Step-by-step explanation:

A probability is the number of desired outcomes divided by the number of total outcomes.

-How many different outfits can Omar put together?

For each t-shirt, that are two options of shorts.

There are 3 t-shirts.

3*2 = 6

Omar can put together 6 outfits.

What is the probability of Omar’s outfits including a red T-shirt or red shorts?

Red t-shirt and red shorts

Red t-shirt and black shorts

Green shirt and red shorts

Yellow shirt and red shorts

4 desired outcomes.

4/6 = 0.6667

66.67% probability of Omar’s outfits including a red T-shirt or red shorts

Please answer this correctly

Answers

Answer: 363 cm squared

Step-by-step explanation:

So we can split the shape into 1 triangle and 3 rectangles.

We can start with the top right rectangle which is a 4 by 5.

4*5 = 20 cm squared

We can now do the horizontal rectangle. We need to find the dimensions firs by subtracting 4 from 31 to find the length and add 4 and 5 to find the height.

This means the dimensions are 27 by 9.

27 * 9 = 243 cm squared

Now the final square toward the bottom left will be a 10 by 7.

10 * 7 = 70 cm squared.

Now for the final piece is the triangle in the bottom left. We need to first find the height which we can determine by taking the the right hand side values of 10 , 4 and 5 and adding those together then subtracting that number by 13 to get the missing length that will add to 6 to find the height.

10 + 4 + 5 = 19

19 - 13 = 6

6 + 6 = 12

Now that we have the height and base of the triangle we solve for the area.

0.5 * 5 * 12 = 30 cm squared

Now we add all the areas together to find the total area.

20 + 243 + 70 + 30 = 363 cm squared

Dustin is buying carpet for the living room. How many square feet of carpet will he need to buy?



Answers

Complete Question:

Dustin is buying carpet for the living room. If the length of the room is 21 ft and the width

is 11 ft, how many square feet of carpet does he need to buy?

Answer:

231 ft²

Step-by-step explanation:

==>GIVEN:

Length of room (L) = 21 ft

Width of room (W) = 11 ft

==>REQUIRED:

Square feet of carpet to be bought = area of the rectangular room

==>SOLUTION:

The room to be covered with carpet is rectangular in shape. In order to ascertain the square feet of carpet to be bought, we need to calculate the area of the room by using the formula for area of rectangle.

Thus, area of rectangle (A) = Length (L) × Width (W)

A = 21 × 11

A = 231 ft²

Square feet of carpet to be bought = 231 ft²

Ania kupiła w księgarni dwie książki i zapłaciła 37,20, a jurek za swoje zapłacił trzy razy więcej. Ile zapłacił jurek

Answers

Answer:

111.60

Question:

Ania bought two books in a bookstore and paid 37.20, and Jurek paid three times more for his. How much did Jurek pay?

Step-by-step explanation:

This is a question on multiplying decimals by natural numbers.

Number if books bought by Ania = 2

Cost for the two books = 37.20

Jurek paid = 3 times the amount Ania paid

Amount Jurek paid = 3×37.20

To multiply decimals with whole numbers, first multiply without the decimals

3×3720 = 11160

3 has no decimal place

37.20 has 2 decimal place

Therefore the answer would be in two decimal place = 111.60

So 3× 37.2= 111.60

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HELP! Find the exact area and circumference of a circle whose diameter is 8 meters. Show your work!! What is the general process of how laws are made in the United States Adam earns $45,000 in his first year as an accountant and earns a 3% increase in eachsuccessive year.(a) Write a geometric series formula,n S, for Adams total earnings overnyears.(b) Use this formula to find Adams total earnings for her first 12 years of his job, to the nearestcent. Which statement is true about the Qin dynasty A) it was successful because of Confucianism. B) it was a feudal state which became a great empire. C) it was followed by the warring states period. D) it failed because of Confucianism. A rich donor gives a hospital $ 960 comma 000 one year from today. Each year after that, the hospital will receive a payment 5 % larger than the previous payment, with the last payment occurring in ten years' time. What is the present value (PV) of this donation, given that the interest rate is 9 %? Can anybody answer these questions Why did Louis riel start two provisional governments Using the ruler postulate, find the distance between 9 and 2. cell engulfs microorganisms in cell "eating":pinocytosisactive transportphagocytosispassive diffusionfacilitated diffusion How has the scene and atmosphere around the Forum changed from the opening of act 1 to its close? The Forum does not change from the opening to the close of the play. Act 1 opens with the Forum in celebration and ends with it in chaos. Act 1 opens with the Forum in chaos and closes with it in celebration. Act 1 opens with the Forum saddened by the Feast of Lupercal and closes with the citizens still saddened because of the thunderstorm. how did Mohandas Gandhi influence MLK Jr.? A German scientist, George Ohm, discovered the relationship between current, voltage, and resistance. This became known as Ohm's law. According to Ohms law, if V is voltage, I is current, and R is resistance, their relationship is expressed by the equation 6th grade math help me. :D..... ^9 belongs to what family of real numbers? Can someone help me out? Solve for x.-3+85-5=-8A. -2.B.-1C.-3/4D.0 7. Tyson obtained a loan from the bank at 7.5% simple interest for 2. 5 years. If the simple interest wasN$347.50, how much did he borrow?8. Hilma invested N$20 000 on 01/01/2018 at 9.5 % interest p.a compounded semi-annually.How much will she receive by 01/01/2022? A bag contains some number of marbles. It is known that 20 of them are red. When 15 marbles are drawn, without replacement, we get 6 red. Assuming E(X)=6 red, what is the total number of marbles in the bag? When a saturated solution of NH4Br dissolved in 100 grams of water is cooled from 60C to 30C, how much NH4Br will precipitate? Two waves with amplitudes of 52 units and 98 units come together. Their amplitude, which is measured at a specific point and time, is 46 units. What wave behavior explains this value? A. destructive interference B. constructive interference C. refraction D. diffraction E. partial transmission