Use the information in Example 7.9, but change the sample size to 144. Quiz
The question sheet
Reveal any answer as you study-
In Solution 7.10, what is the value of σ (the standard error) used?
- 0.05
- 2
- 0.5
- 5
Reveal answer
Answer: 0.05
Source evidence
PDF page 422: Solution 7.10 0.5 σ = = 0.05. Therefore:
-
What is the value of μx (the sample mean) in Solution 7.10?
- 2
- 0.5
- 0.05
- 200
Reveal answer
Answer: 2
Source evidence
PDF page 422: a. We have, μx = μ = 2 and σx =
-
What is the 50th percentile for the sample mean time?
- 200
- 2.03
- 1.97
- 2
Reveal answer
Answer: 2
Source evidence
PDF page 422: 1. 50 percentile = μx = μ = 2
-
What is the value of μΣx, the mean of the sums?
- 2
- 5
- 200
- 100
Reveal answer
Answer: 200
Source evidence
PDF page 422: b. We have μΣx = n(μx) = 100(2) = 200 and σμx = n (σx) = 10(0.5) = 5. Therefore
-
What is the standard deviation of the sums, σΣx?
- 10
- 200
- 5
- 0.05
Reveal answer
Answer: 5
Source evidence
PDF page 422: b. We have μΣx = n(μx) = 100(2) = 200 and σμx = n (σx) = 10(0.5) = 5. Therefore
-
What is the 50th percentile for the sum of sample times?
- 2
- 203.37
- 200
- 196.63
Reveal answer
Answer: 200
Source evidence
PDF page 422: 1. 50 percentile = μΣx = n(μx) = 100(2) = 200
-
What is P(1.75 < x < 1.85) for the sample mean?
- 0.05
- 0.25
- 0.0013
- 0.75
Reveal answer
Answer: 0.0013
Source evidence
PDF page 422: c. P(1.75 < x < 1.85) = normalcdf(1.75,1.85,2,0.05) = 0.0013
-
What is the value two standard deviations above the sample mean?
- 2.1
- 2.5
- 2.0
- 2.03
Reveal answer
Answer: 2.1
Source evidence
PDF page 422: , and solving for x, we have x = 2(0.05) + 2 = 2.1
-
What is the IQR for the sum of the sample times?
- 196.63
- 203.37
- 6.74
- 0.05
Reveal answer
Answer: 6.74
Source evidence
PDF page 422: e. The IQR is 75 percentile – 25 percentile = 203.37 – 196.63 = 6.74
-
How is the IQR for the sum calculated in part e?
- 203.37 - 196.63
- 2.03 - 1.97
- 100 x 2
- 200 - 5
Reveal answer
Answer: 203.37 - 196.63
Source evidence
PDF page 422: e. The IQR is 75 percentile – 25 percentile = 203.37 – 196.63 = 6.74
-
In the sexual assault problem, what is the assumed standard deviation?
- 2 minutes
- 0.05 minutes
- 100 minutes
- 0.5 minutes
Reveal answer
Answer: 0.5 minutes
Source evidence
PDF page 422: In the United States, someone is sexually assaulted every two minutes, on average, according to a number of studies. Suppose the standard deviation is 0.5 minutes and the sample size is 100.
-
In the sexual assault problem, what is the sample size?
- 144
- 10
- 100
- 50
Reveal answer
Answer: 100
Source evidence
PDF page 422: In the United States, someone is sexually assaulted every two minutes, on average, according to a number of studies. Suppose the standard deviation is 0.5 minutes and the sample size is 100.
Introductory Statistics
Introductory Statistics by OpenStax, used under CC BY 4.0. Changes made by Stratacademy.
Make your own — free
Turn any notes into a game in under a minute. Free to start.