Mathematics, 21.09.2019 17:10 foriegnngal

The city was concerned that brink's was stealing money from the parking meter receipts. assume that this sample of months is like a random sample. given your answers to the first two parts, what is the probability of a sample at least as far below the mean as the sample from the period of the brink's contract?

Answers: 1

Show answers

Answers

Question 1:
Cheap-As-Dirt Rental Company advertises that the average cost of a rental they find for undergraduate students at the University of Oregon is $540 with a standard deviation of $75 (Let us assume the rents are approximately Normally distributed.) The Department of Consumer Protection will investigate the company if, when they choose a sample of students, they find that the average rental cost for those students is $610 or more.

Part (a):

Assuming that the company is advertising truthfully, what is the probability that the company will be investigated if the Department of Consumer Protection only samples one client?

The probability that an n sample of a normally distributed dataset with a mean, μ, and standard deviation, σ, exceeds a value x, is given by

$P(X\ \textgreater \ x)=1-P(X\ \textless \ x)=1-P\left(z\ \textless \ \frac{x-\mu}{\frac{\sigma}{\sqrt{n}}} \right)$

If one client is sampled, then

$P(X\ \textgreater \ 610)=1-P\left(z\ \textless \ \frac{610-540}{\frac{75}{\sqrt{1}}} \right) \\ \\ =1-P\left(z\ \textless \ \frac{70}{\frac{75}{1}} \right)=1-P\left(z\ \textless \ \frac{70}{75} \right) \\ \\ =1-P(z\ \textless \ 0.9333)=1-0.82468=\bold{0.1753}$

Part (b):

Assuming that the company is advertising truthfully, the probability that the company will be investigated if the Department of Consumer Protection samples 10 clients is given by:

$P(X\ \textgreater \ 610)=1-P\left(z\ \textless \ \frac{610-540}{\frac{75}{\sqrt{10}}} \right) \\ \\ =1-P\left(z\ \textless \ \frac{70}{\frac{75}{3.162}} \right)=1-P\left(z\ \textless \ \frac{70}{23.72} \right) \\ \\ =1-P(z\ \textless \ 2.951)=1-0.99842=\bold{0.0016}$

Part (c):

Assuming that the company is advertising truthfully, the probability that the company will be investigated if the Department of Consumer Protection samples 50 clients is given by:

$P(X\ \textgreater \ 610)=1-P\left(z\ \textless \ \frac{610-540}{\frac{75}{\sqrt{50}}} \right) \\ \\ =1-P\left(z\ \textless \ \frac{70}{\frac{75}{7.071}} \right)=1-P\left(z\ \textless \ \frac{70}{10.61} \right) \\ \\ =1-P(z\ \textless \ 6.5997)=1-1=\bold{0}$

Question 2. In New York City in the late 1970s and early 1980s, parking meter collections averaged $1.75 million per month with a standard deviation of $302 thousand per month. Assume that the amount generated per month is Normal with the mean and standard deviation from the previous sentence. For about two years the city hired Brink’s Inc. to do collections instead. The data file gives the collections that Brink’s reported to the city during that period.

Part (a):

The sample size for this data is the number of months in two years which is 24 months.

Part (b):

The sample mean is given by the average of the data in the datafile. This is obtained by adding the data in the datasheet and dividing the result by 24.

Thus sample mean is given by

$(1330143+1525370+1312257+1494717+1385822+1557598+ \\ 
1469066+1547011+1565671+1124576+1773806+1652490+ \\ 
1744558+1678286+1636597+1738847+1576383+1846508+ \\ 
1746899+1685611+1794467+1695017+1671626+1566107) / 24 \\ \\ = 
\frac{38,119,433}{24} =\$1,588,309.71$

Part (c):

The city was concerned that Brink’s was stealing money from the parking meter receipts. Assuming that this sample of months is like a random sample. Given the answers to the first two parts, the probability of a sample at least as far below the mean as the sample from the period of the Brink’s contract is given by

$P(X\ \textless \ 1,588,309.71)=P\left(z\ \textless \ \frac{1,588,309.71-1,750,000}{\frac{302,000}{\sqrt{24}}} \right) \\ \\ =P\left(z\ \textless \ \frac{-161,690.29}{\frac{302,000}{4.899}} \right)=P\left(z\ \textless \ \frac{-161,690.29}{61,645.49} \right)=P(z\ \textless \ -2.623) \\ \\ =\bold{0.0044}$

Answer from: Quest

part a

x y

0 8

1 7.5

2 7

3 6.5

4 6

5 5.5

for every hour i deducted .5 inches from the length of the candle

part b

it is a function because for every x value there is only one y value

part c

for every x value there is only one y value

x y

0 8

1 7.6

2 7.2

3 6.8

step-by-step explanation:

Answer from: Quest

well your weight will go up if you are not going to burn the calories/ carbs

step-by-step explanation:

Another question on Mathematics

Mathematics, 21.06.2019 16:30

To which set of numbers does the number –5 belong? select all that apply. integers natural numbers rational numbers real numbers whole numbers

Answers: 1

Answer

Mathematics, 21.06.2019 16:30

The angles below are supplementary. what is the value of x? a pair of supplementary angles is shown. one angle measures 7x + 33, and the other angle measures 70. 5.3 8.14 11 14.7

Answers: 1

Answer

Mathematics, 21.06.2019 17:00

Complete the equation of the line through (−10,3) and (−8,−8). use exact numbers.

Answers: 1

Answer

Mathematics, 21.06.2019 17:00

Ataxi company charges $2.25 for the first mile and then $0.20 per mile for each additional mile, or f = $2.25 + $0.20(m - 1) where f is the fare and m is the number of miles. if juan's taxi fare was $6.05, how many miles did he travel in the taxi? if juan's taxi fare was 7.65, how many miles did he travel in taxi

Answers: 1

Answer

You know the right answer?

The city was concerned that brink's was stealing money from the parking meter receipts. assume that...

Questions

Mathematics, 28.03.2020 04:49

Kala earns Al dollars each week working part-time at a bookstore. She earns one additional dollar for each book that she sells. Le A be the amou...

Mathematics, 28.03.2020 04:49

Belinda is thinking about buying a house for $179,000. The table below shows the projected value of two different houses for three years:...

Mathematics, 28.03.2020 04:49

What is the slope and y-intercept of y = 1/4x + 8...