AP Statistics
Practice- Hypothesis Test and CI Practice #1
One Population
Name:____________________________________
Date:_____________________________________
1.
Mike took 57 free throws. He made 31 of them. Use a 0.05 significance level to test the claim that the
population proportion of makes is greater than 50%.
2.
A sample of 11 paperback books was randomly selected from a population of paperback books in an
English classroom at Mahopac High School and the number of pages was recorded for each. Use a 0.01
significance level to test the claim that the population mean number of pages per books in the classroom
is different from 400 pages.
500
502
471
451
258
422
460
406
492
534
345
3.
Suppose that a production process is considered to be out of control if more than 3% of the items
produced are defective. Inspection of a random sample of 500 items produced in a particular week
revealed that 25 were defective. Use a 0.05 significance level to test the claim that the process was out
of control during that week. Construct a 95% confidence interval estimate of the population proportion
of defects during any given week.
4.
Recorded here are the germination times (number of days) for seven seeds of a new strain of snap bean.
12
16
15
20
17
11
18
Test the claim that the population mean number of germination days is more than 15 at the 0.01
significance level. Construct a 95% confidence interval estimate for the true mean germination time for
this strain.
AP Statistics
Answer Key- Hypothesis Test and CI Practice #1
One Population
Answer Key
1.
n = 57
x = 31
H 1 : p > 0.5
H 0 : p = 0.5
α = 0.05
Use stat test #5
Name:____________________________________
Date:_____________________________________
P-value= 0.254
P − value > α ∴ Don' t reject H 0
There is insufficient evidence to reject the claim that the population proportion of made free throws is 0.5 at the
0.05 significance level. Therefore, the claim that it is greater is false.
2.
H 1 : µ ≠ 400
Input data into L1
Use stat test #2 (select “data”)
P-value= 0.128
P − value > α ∴ Don' t reject H 0
H 0 : µ = 400
There is insufficient evidence to reject the claim that the population mean number of pages is 400 at the 0.01
significance level. Therefore, the claim that it is different is false.
3.
n = 500
x = 25
α = 0.05
H 1 : p > 0.03
H 0 : p = 0.03
P-value= 0.00438
Use stat test #5
P − value < α ∴ reject H 0
There is sufficient evidence to reject the claim that the population proportion of defects is 3% at the 0.05
significance level. Therefore, the claim that it is greater is true (process is out of control).
CI= 95%
Use stat test #A
(0.0309, 0.0691)
We are 95% confident that the population proportion of defects is between 3.09% and 6.91%.
4.
Input data into L1
Use stat test #2 (select “data”)
P-value= 0..327
P − value > α ∴ Don' t reject H 0
H 1 : µ > 15
H 0 : µ = 15
There is insufficient evidence to reject the claim that the population mean number of days for germination is 15
at the 0.01 significance level. Therefore, the claim that it is greater is false.
CI= 95%
Use stat test #8
(12.605, 18.537)
We are 95% confident that the population mean germination time is between 12.605 and 18.537 days.