By using the P-value method, we conclude that, fewer than half of Americans prefer to watch the news rather than read or listen to it.
What is p-value?
In statistics, the p-value is a probability value that measures the evidence against a null hypothesis. It is the probability of observing a test statistic as extreme as, or more extreme than, the actual test statistic, assuming that the null hypothesis is true.
In this problem, we want to test the claim that fewer than half of Americans prefer to watch the news, based on a poll of 1075 Americans where 46.8% of the respondents said they prefer to watch the news.
Let p be the true proportion of Americans who prefer to watch the news. Then the null hypothesis is:
H0: p ≥ 0.5 (more than or equal to half of Americans prefer to watch the news)
The alternative hypothesis is:
Ha: p < 0.5 (fewer than half of Americans prefer to watch the news)
We will use the normal distribution as an approximation to the binomial distribution, since n = 1075 is large and the success-failure condition is satisfied. The expected number of respondents who prefer to watch the news is:
E = np = 1075 × 0.468 = 503.1
The standard deviation of the sampling distribution of p is:
σ = sqrt[(p(1-p))/n] = sqrt[(0.5×0.5)/1075] ≈ 0.015
We can now calculate the z-score for the sample proportion:
z = (x - E) / σ = (1075 × 0.468 - 503.1) / 0.015 ≈ -4.28
where x is the observed number of respondents who prefer to watch the news, which is 1075 × 0.468 ≈ 503.
The P-value for this test is the probability of getting a z-score less than or equal to -4.28 under the standard normal distribution. Using a standard normal table or calculator, we find that this probability is very close to 0. Therefore, the P-value is less than 0.10, the chosen significance level.
Since the P-value is less than the significance level, we reject the null hypothesis. We have sufficient evidence to conclude that fewer than half of Americans prefer to watch the news rather than read or listen to it.
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Cole, a caterer, is investing some money in equipment and employees to help grow his business. Recently he spent $100 on equipment and hired a server who makes $16 per hour. Cole is hoping to make up these expense at the next job that is scheduled, which pays a base of $50 in addition to $18 per hour that the server works. In theory, this event could pay enough to cancel out Cole's expenditures. How much would the job pay? Write a system of equations, graph them, and type the solution.
The job would need to pay $500 to cover Cole's expenses.
What is probability?
Probability is a measure of the likelihood of an event occurring. It is a number between 0 and 1, where 0 means the event is impossible and 1 means the event is certain to happen.
Let's define some variables to represent the unknowns in this problem:
Let x be the number of hours that the server will work at the next job.
Let y be the total amount of money that Cole will make from the next job.
With these variables, we can set up a system of equations:
The cost of the equipment and server hire is $100 plus the server's hourly wage multiplied by the number of hours worked:
100 + 16x = total cost
The amount that Cole will make from the next job is the base pay of $50 plus the server's hourly wage multiplied by the number of hours worked:
y = 50 + 18x
We want to find the value of y that will make up for the $100 expense. In other words, we want to find the value of x that satisfies the equation:
total cost = y
Substituting the second equation into the first equation, we get:
100 + 16x = 50 + 18x
Solving for x, we get:
x = 25
Substituting x = 25 into the second equation, we get:
y = 50 + 18(25) = 500
Therefore, the job would need to pay $500 to cover Cole's expenses.
We can graph the two equations to visualize the solution:
y = 50 + 18x y = 100 + 16x
-------------------- --------------------
x = 0 | 50 | | 100 |
| | | |
| | | |
| | | |
| | | |
-------------------- --------------------
25 25
The point where the two lines intersect is (25, 500), which represents the solution to the system of equations.
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Tara invests $555 into a savings account that has an interest rate of 12.6% and is compounded quarterly. How many years will it take for the account to reach a balance of $5,600?
a. 18.6 years
b. 10.7 years
c. 18.0 years
d. 17.3 years
Tara invests $555 into a savings account that has an interest rate of 12.6% and is compounded quarterly. It will take 18.6 years for the account to reach a balance of $5,600.
What do you mean by interest rate?The amount that the lender charges the client above and beyond the initial amount is referred to as the interest rate. Given the time worth of money, a person who deposits money in a bank or other financial organisation also gets extra revenue known as interest received by the depositor.
Using the quarter compound formula given below-
[tex]$ \rm A = P (1 + \frac{r}{4})^{4 \times t}[/tex]
Where,
Interest in a year (r)= 12.6% = 12.6/100= 0.126
Actual amount (P)= $555
Final amount (A)= $5,600
Lets solve:
[tex]5,600 = 555(1+0.126/4)^{4t[/tex]
Or, [tex](4.126/4)^{4t}= 5600/555[/tex]
Or, 4t ln(4.126/4)= ln 5600/555
Or, 4t =74.532
Or, t ≈ 18.6
Hence the correct answer is 18.6 years
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The table gives the number of cellular telephone subscribers in a country (in thousands) from 2007 through 2012. Find the average annual rate of change during this time period.
The average annual rate of change during the time period 2007-2012 is
I Need help ASAP!!!!!!
Rounding to the nearest unit, the average annual rate of change during this time period is 10,797.
What is equation?An equation is a mathematical statement that shows that two expressions are equal. It typically contains variables, coefficients, and mathematical operations such as addition, subtraction, multiplication, and division. An equation can be solved to find the value of the variable that makes the statement true. Equations are used in many areas of mathematics and science, as well as in everyday life, to model relationships and solve problems.
Here,
To find the average annual rate of change, we need to calculate the total change in subscribers over the 6-year period and divide by the number of years. The total change is the final value minus the initial value, or:
335,244 - 270,461 = 64,783
The number of years is 6.
So the average annual rate of change is:
64,783/6 = 10,797.17
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what are two numbers whose product is 52 and whose sum is 11?
Answer:
There are no two numbers whose product is 52 and whose sum is 11.
Step-by-step explanation:
give the 1st number is x and the 2nd number is y, then
x + y = 11 and xy = 52
x + y = 11 => y = 11 - x
x(11 - x) = 52
11x - x^2 = 52
=> x^2 - 11x + 52 = 0
Using quadratic formula: ax^2 + bx + c = 0
with a = 1, b = -11, c = 52
=> x = [-b ± √(b^2 - 4ac)]/2a
=> x = [-(-11) ± √((-11)^2 - 4x1x52)]/2x1
=> x = [11 ± √(121 - 208)]/2
=> x = [11 ± √(-87)]/2
Since the square root of a negative number is not a real number, there are no real solutions to this equation. Therefore, there are no two numbers whose product is 52 and whose sum is 11.
Four part spinner is spun twice total number of possible outcomes
please help me i need to get these right
Answer:
13
Hope this helps!
Step-by-step explanation:
can yall help me i dont get it
According to the given information, the equation that represents the proportional relationship is y = (1/4)x
What is proportion?
Proportion is a mathematical concept that describes the equality of two ratios. In other words, it is a statement that two ratios or fractions are equal.
For example, if we have two fractions, a/b, and c/d, we can say that they are in proportion if:
a/b = c/d
We can see that the ratio between X and Y is always 4:1, which means that Y is one-fourth of X. We can write this as:
Y = (1/4)X
Therefore, the equation that represents the proportional relationship is:
y = (1/4)x
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5.
What is the width of a rectangle if the area is 2x²-x-6 and the length is 2x + 3?
O-x-1--
x-2
3
2x+3
O-x+ 2
MacBook Air
2x²-1
2
Onone of the answer choices
Answer: x-2
Use A=Lw
A/L=w
if you factor and cancel, you are left wirh x-2.
In a study with randomly selected participants, it was found that "45.3 % of adults report that they live with one or more chronic conditions". The study also reported a margin of error 3.5 %. Create a 95% confidence interval for the proportion of all U.S. adults living with chronic conditions. don't round.
To create a 95% confidence interval for the proportion of all U.S. adults living with chronic conditions, we can use the following formula:
CI = p ± zsqrt(pq/n)
where:
p is the sample proportion (0.453)
q is the complement of p (1 - p = 0.547)
z is the z-score associated with a 95% confidence level (1.96)
n is the sample size (unknown)
We need to find the sample size (n) in order to calculate the confidence interval. We can do this by using the margin of error formula:
ME = zsqrt(pq/n)
where ME is the margin of error (0.035)
Solving for n, we get:
n = (z^2 * p * q) / ME^2 = (1.96^2 * 0.453 * 0.547) / 0.035^2 = 580.04
Rounding up to the nearest whole number, the sample size is 581.
Now we can substitute the values into the confidence interval formula:
CI = 0.453 ± 1.96sqrt(0.4530.547/581)
CI = 0.453 ± 0.035
The 95% confidence interval for the proportion of all U.S. adults living with chronic conditions is:
CI = (0.418, 0.488)
So we can say with 95% confidence that the true proportion of all U.S. adults living with chronic conditions is between 0.418 and 0.488.
Find the centre and radius of
x^2 + y^2 = 49
Answer:
center:(0,0)
Radius:7
Step-by-step explanation:
the equation of circle:
(x-h)^2+(y-k)^2=r^2
the point h and k are the center of the circle
(h,k) ———-> (0,0)
since r^2 =49
So, the radius will be the square root of that number
[tex]r^{2} =49[/tex]
[tex]\sqrt{r^{2} } =\sqrt{49}[/tex]
[tex]r=7[/tex]
A 25% orange juice drink is mixed with a 100% orange juice drink. The function f(x)=
concentration of orange juice in the drink after a gallons of the 25% drink are added to 4 gallons of pure juice.
(4)(1.0)+z(0.25) models the
4+2
What will be the concentration of orange juice in the drink if 2 gallons of 25% drink are added? Give the answer as a percent
but do not include the percent sign (%).
We need to mix 3.2 units of the 25% orange juice with 0.8 Units of the 100% orange juice to get a 4-unit mixture with a 25% concentration of pure orange juice.
The first thing we need to do is figure out how much of each type of orange juice we need to mix together to get the desired 25% concentration. Let's call the amount of the 25% orange juice "x" and the amount of the 100% orange juice "y".
We know that the total amount of juice we want to end up with is "4" (since the function f(x) is equal to 4 + 2). So we can write an equation based on that:
x + y = 4
We also know that we want the final concentration to be 25%, which means that the amount of pure orange juice in the mixture should be 25% of the total volume. To calculate that, we can use the formula:
0.25 = (0.25x + y) / 4
Simplifying that equation, we get:
0.25x + y = 1
Now we have two equations with two unknowns (x and y), which we can solve using substitution or elimination. I'll use substitution here:
x = 4 - y (from the first equation)
0.25(4 - y) + y = 1 (substituting for x in the second equation)
1 - 0.25y + y = 1
0.75y = 0
y = 0
Uh-oh, that's not good. It looks like we can't use any of the 100% orange juice, or we'll end up with a concentration greater than 25%. Let's double-check our equations and see if there's a mistake.
x + y = 4
0.25x + y = 1
Hmm, it looks like we made a mistake in the second equation. The 0.25x term should be multiplied by the concentration of the 25% orange juice, which is 0.25 (or 25% as a fraction). So the correct equation should be:
0.25(0.25x) + y = 1
Now let's solve for y:
0.0625x + y = 1
y = 1 - 0.0625x
Substituting that into the first equation, we get:
x + (1 - 0.0625x) = 4
0.9375x = 3
x = 3.2
So we need to mix 3.2 units of the 25% orange juice with 0.8 units of the 100% orange juice to get a 4-unit mixture with a 25% concentration of pure orange juice.
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HELP NEED THIS ASAP PLS HELP
Answer:
B
Step-by-step explanation:
Given:
1 furlong has 660 feet
1 yard has 0,5 fathom
Find:
How many fathoms are there in one furlong?
.
We know that 1 yd has 3 ft, that means:
There's 660 ft in one furlong and 3 ft in 0,5 of a fathom (6 ft in one fathom)
Now, in order to find how many fathoms are there in one furlong, we have to divide the number of feet in a furlong by the number of feet in a fathom:
[tex] \frac{660}{6} = 110 \: fathoms[/tex]
Jacob's lock combination is a 3 digit number. If the digits cannot repeat, the product of the digits is 84, and the digits are increasing from left to right, how many combinations can Jacob have?
There are 5 possible combinations for Jacob's lock combination with increasing digits from left to right, and the product of the digits being 84.
What is multiplication ?Multiplication is a mathematical operation that involves combining two or more quantities to find their total or product. It is often represented by the "x" symbol or the multiplication sign "⋅". Multiplication is a fundamental operation in arithmetic and is used to calculate the total or result of repeated addition or groups of equal quantities.
According to the given information:The product of the digits being 84 implies that the possible combinations of digits are limited to those whose product is 84. The prime factorization of 84 is 2^2 * 3 * 7. Since the digits must be increasing from left to right and cannot repeat, the possible combinations of digits are:
1, 2, 42
1, 3, 28
1, 4, 21
2, 3, 14
2, 6, 7
So, there are 5 possible combinations for Jacob's lock combination.
Therefore, There are 5 possible combinations for Jacob's lock combination with increasing digits from left to right, and the product of the digits being 84.
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The painting shown at the right
has an area of 360 in2. What is
the value of x?
X =
(3x + 2) in.
Answer:
x = 10.20240940
Step-by-step explanation:
[tex]x(2x + 9) = 2x^2 + 9x[/tex]
[tex]2x^2 + 9x = 300[/tex]
- 300 on both sides
[tex]2x^2 + 9x - 300 = 0[/tex]
solve using the quadratic formula
[tex]x = -b +/- \ \text{all root} (b)^2 - 4(a)(c) \ \text{All over} \ 2(a)[/tex]
When all the values are plugged in:
When using "+" in the equation you should get:
x = 10.20240940
When using "-" in the equation you should get:
x = −14.70240940
Now.. you CANNOT have a negative length, so you cross of the negative value leaving you one value for x which is 10.20240940.
Your answer is: x = 10.20240940
ohn spent 20% of his money on food. He spent 2/5 of the remainder on a toy. The toy cost $12.
(a) What percentage of his money did he spend on the toy?
(b) How much money did he have at first?
Toy Cost Percentage
Aditya Kashyap
ohn spent 20% of his money on food. He spent 2/5 of the remainder on a toy. The toy cost $12.
(a) What percentage of his money did he spend on the toy?
b) How much money did he have at first?
(a) To find the percentage of his money that John spent on the toy, we need to first find the total amount of money he had left after spending 20% on food.
Let's say John had x amount of money initially.
Then, he spent 20% of x on food, which is 0.2x.
So, he had (x - 0.2x) = 0.8x amount of money left.
Next, he spent 2/5 of this remaining amount on a toy, which cost $12.
Therefore, 2/5 of 0.8x = $12
Simplifying this, we get:
0.32x = $12
x = $37.50
So, John had $37.50 initially.
Now, to find the percentage of his money that he spent on the toy, we can use the formula:
Percentage = (Amount spent on toy / Total initial amount) x 100
Amount spent on toy = $12
Total initial amount = $37.50
Plugging these values into the formula, we get:
Percentage = (12 / 37.50) x 100
Percentage = 32%
Therefore, John spent 32% of his money on the toy.
(b) John had $37.50 at first.
try to evaluate the logarithm
(a) log5^25
What is the inverse probability of drawing either an 8 or a 9 from a deck of cards?
The inverse probability of drawing either an 8 or a 9 from a deck of cards is 0.852.
What is probability?
The likelihood of an occurrence can be determined using probability. It can only be applied to determine how likely an event is to occur. a scale with 0 being impossible and 1 being a specific occurrence.
We know that there are 52 cards in a deck consisting of 4 cards of each number.
So,
⇒ Probability of drawing 8 = [tex]\frac{4}{52}[/tex]
⇒ Probability of drawing 8 = [tex]\frac{1}{13}[/tex]
Similarly,
⇒ Probability of drawing 9 = [tex]\frac{4}{52}[/tex]
⇒ Probability of drawing 9 = [tex]\frac{1}{13}[/tex]
Now,
Let event A be drawing a 8 and event B drawing a 9.
So,
⇒ P (A ∪ B) = [tex]\frac{1}{13}[/tex] + [tex]\frac{1}{13}[/tex] - ([tex]\frac{1}{13}[/tex] * [tex]\frac{1}{13}[/tex] )
⇒ P (A ∪ B) = [tex]\frac{2}{13}[/tex] - [tex]\frac{1}{169}[/tex]
⇒ P (A ∪ B) = [tex]\frac{25}{169}[/tex]
⇒ P (A ∪ B) = 0.148
Inverse probability = 1 - 0.148
Inverse probability = 0.852
Hence, the inverse probability of drawing either an 8 or a 9 from a deck of cards is 0.852.
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Convert 5.3 cubic yards to cubic inches
Answer:
247277 cubic in
Step-by-step explanation:
Destiny checked the remaining stock for each garment sold at the store where she worked.
For 7 garments, there remained:
5 items 4 items 5 items 3 items 8 items 5 items 5 items
What was the mean amount of remaining stock?
The mean of the remaining stock is 5
How to find the meanTo find the mean amount of remaining stock, we need to add up the amounts of remaining stock for each garment and divide by the total number of garments.
So, we can start by adding up the amounts of remaining stock:
5 + 4 + 5 + 3 + 8 + 5 + 5 = 35
Now we can divide by the total number of garments (which is 7) to find the mean:
35 / 7 = 5
Therefore, the mean amount of remaining stock is 5.
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The distance from a driveway to the closest house is 12,672 feet. How far is that in miles? (1 mile = 5280 feet)
Responses
Answer: 2.4
(Hopefully this helps! If you can, please mark me brainliest tomorrow)
Explanation:
We divide the feet by 5280 to find that amount in miles.
12,672/5280 = 2.4
Therefore, the answer is 2.4 miles.
WILL GIVE TRUE 100 POINTS AND BRAINLYEST FOR THE CORRECT ANSWER
Answer:
B. S(15) - S(10) = -40 means that there were 40 less students in 2010 than there were in 2015. This statement is true because S(15) represents the number of students in the year 2015, and S(10) represents the number of students in the year 2010. Subtracting S(10) from S(15) gives the change in the number of students over that 5-year period.
C. S(0) = 2,000 means that there were no students in the year 2000. This statement is also true because S(t) represents the number of students in terms of the number of years after 2000. Therefore, S(0) represents the number of students in the year 2000, which is the starting point for the function.
Step-by-step explanation:
“Number line” 1⁄2, 3⁄4, 60%, .56, 85%. Place the largest and smallest product between 2 of the values on the number line. Place the largest and smallest quotient between 2 of the values on the number line.
The numbers "1⁄2, 3⁄4, 60%, .56, 85% " are represented on number line such as given below in figure.
A number line is a pictorial representation of numbers on a straight line. It’s a reference for comparing and ordering numbers. It can be used to represent any real number that includes every whole number and natural number. Just to recollect, the whole number is a set of numbers that include all counting numbers (1, 2, 3,4,5,6 …….) and zero (0), whereas the natural number is the set of all counting numbers i.e. 1, 2, 3, 4, 5, 6……..
Writing numbers on a number line make it easier to compare the numbers. From the above figure, we can see that the integers on the left side are smaller than the integers on the right side. For example, 0 is less than 1, -1 is less than 0, -2 is less than -1, and so on.
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What is the equation answer of 63.4 divided by 20?
Answer:
3.17
Step-by-step explanation:
First change 63.4 to 634/10
Then simplify
You get 317 over 5 then divide by 20 and get
3.17000
Then round
help answer math question please
Answer:f(2)=27
g(-4)=3
h(3)=28/9
Step-by-step explanation:
f(x)=-3I x- 11 I, when f(2)
f(2)= -3 I 2-11 I
f(2)= -3 I -9 I
f(2)= -3*-9
f(2)=27
g(x)=1 + the square root of x+8, when g(-4)
g(-4)=1+the square root of -4+8
g(-4)=1 + the sqaure root of 4( 2= the sqaure root of 4 )
g(-4)=1+ 2
g(-4)=3
h(x)=3x^2 +1/ x^2, when h(3)
h(3)=3(3)^2 +1/ 3^2
h(3)=3(9)+1/9
h(3)=28/9
HOPE IT HELPS :)
BRAINLIEST PLEASE ANSWER Use the form, ( the brackets mean absolute value) [x-b] <= c to write a absolute value inequality that has the solution set x<9 or x>=-5.
absolute value inequality |x - 2| <= 7 and (x <= 9 or x >= -5)
how to create an absolute value inequality?To create an absolute value inequality that has the solution set x < 9 or x >= -5, we first need to find the midpoint between -5 and 9, which is:
Midpoint = (-5 + 9) / 2 = 2
now, we need to find the distance between the midpoint and either endpoint.
Distance = |9 - 2| = 7
Now we can use the formula:
|x - b| <= c
where b is the midpoint and c is the distance.
putting the values we found,
|x - 2| <= 7
To get the solution set x < 9 or x >= -5, we can split this inequality into two parts:
x - 2 <= 7 or -(x - 2) <= 7
Simplifying each part, we get:
x <= 9 or x >= -5
Combining the two inequalities we get :
|x - 2| <= 7 and (x <= 9 or x >= -5)
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i want to confirm this logarithm with my answer ,
3 log 4
Answer:
Of course! The value of 3 log 4 is approximately 4.7712. Does that match your answer?
What is a thirty degrees angle
Answer:
A 30 degree angle is an acute angle cause its less than 90 degrees
Answer:
A thirty degree angle is an acute angle.
A thirty degree angle is formed when two lines meet or intercept at a point .
A thirty degree angle is one in which the measure is less than 90 degrees
A display case is shaped like the prism shown below. The bases are right triangles. Find the surface area of the prism.
Answer:
200ft²
Step-by-step explanation:
SA = 8(15) + (8+15+17) 20
= 120+ (4)(20)
= 120+80
= 200ft²
Please guys Help me ASAP!!!
The true statement about the value of a in comparison to 0 and 1 is that it is a real number between 0 and 1.
A graph of y = f⁻¹(x) is shown below.
An equation for f⁻¹(x) is [tex]y=\frac{1}{a^x}[/tex].
What is a decreasing function?For any given function, y = f(x), if the output value (range or y-value) is decreasing when the input value (domain or x-value) is increased, then, the function is generally referred to as a decreasing function.
By critically observing the graph of f(x), we can logically deduce that [tex]a^x[/tex] is positive for all values of x and as such, all values of a must also be positive:
0 < a
Additionally, the exponential function [tex]a^x[/tex] represent a decreasing function, so for any values of x, we have:
[tex]a^x > a^{x+1}[/tex]
1 > a
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Tom is a supermarket manager. He reviewed transaction time when a customer paid by credit card. The
transaction time is normally distribution with mean of 20 seconds and standard deviation of 5 seconds.
(a) For a group of 6 customers, find the probability that 5 customers can finish the transaction within 20
seconds. (Assume that the transaction times of customers are independent.)
After discussion with the network provider, he will upgrade the network so that it is promised that each
transaction time can be reduced by 15%.
(b) Use Y to denote the transaction time after network upgrade. Find the mean and standard deviation of Y.
(c) Calculate the 97th percentile of Y. (i.e. find the value of t such that P(Y
(d) Compare with the transaction time before upgrade, is it (I) a higher proportion, (II) a lower proportion,
or (III) the same proportion of all customers can finish the transaction within 20 seconds? (Just state
your answer, no calculation is needed.)
Answer:
Step-by-step explanation:
(a) We can use the standard normal distribution to solve this problem. We first need to standardize the distribution by using the formula:
Z = (X - μ) / σ
where X is the transaction time, μ is the mean, σ is the standard deviation, and Z is the standard normal variable.
For 5 customers to finish the transaction within 20 seconds, we need to find the probability that 5 out of 6 customers have a transaction time less than or equal to 20 seconds. We can use the binomial distribution to find this probability:
P(X = 5) = 6C5 * (0.5)^5 * (0.5)^1 = 0.2344
where 6C5 is the number of ways to choose 5 customers out of 6.
(b) After the network upgrade, the transaction time will be reduced by 15%, so the new mean and standard deviation are:
μ' = 0.85 * μ = 17 seconds
σ' = 0.85 * σ = 4.25 seconds
(c) To find the 97th percentile of Y, we need to find the value of t such that P(Y ≤ t) = 0.97. Since Y is a normally distributed variable, we can standardize it using the formula:
Z = (Y - μ') / σ'
Then we can find the value of t using a standard normal distribution table or calculator:
Z = 1.88
t = μ' + Z * σ' = 17 + 1.88 * 4.25 = 25.99 seconds
(d) After the upgrade, a higher proportion of customers can finish the transaction within 20 seconds. This is because the mean transaction time has decreased from 20 seconds to 17 seconds, which means that more customers will have a transaction time less than or equal to 20 seconds.