Question

15. A Pew Poll in 2010, found that 50% of adults aged 25-29 had access to only a cell phone, while 40% had access to both a cellphone and landline and 10% had access to only a landline. We wish to conduct a Goodness of Fit Test to see if the results of a poll of a random sample of 130 adults aged 25-29 are significantly different from the 2010 poll results.

The random sample of 130 adults found that 69 had access to only a cell phone, 39 had access to only a landline, and 22 had access to both types of phones.

Which of the following are the correct null and alternative hypothesis for this test?

	A.	Ho: p = 0.50 Ha: p =/= 0.50
	B.	Ho: The distribution is the same as in 2010. Ha: The distribution is different than in 2010.
	C.	Ho: The distribution is different than in 2010. Ha: The distribution is the same as in 2010.
	D.	Ho: pcell=0.33 , pboth=0.33, pland=0.33 Ha: pcell=0.50 , pboth=0.40, pland=0.10

16. A Pew Poll in 2010, found that 50% of adults aged 25-29 had access to only a cell phone, while 40% had access to both a cellphone and landline and 10% had access to only a landline. We wish to conduct a Goodness of Fit Test to see if the results of a poll of a random sample of 130 adults aged 25-29 are significantly different from the 2010 poll results. The table below presents the observed results.

	Cell only	Landline Only	Both
Observed	69	39	22
Expected

Compute the expected count for the "BOTH" cell.

17. A Pew Poll in 2010, found that 50% of adults aged 25-29 had access to only a cell phone, while 40% had access to both a cellphone and landline and 10% had access to only a landline. We wish to conduct a Goodness of Fit Test to see if the results of a poll of a random sample of 130 adults aged 25-29 are significantly different from the 2010 poll results.

The random sample of 130 adults found that 69 had access to only a cell phone, 39 had access to only a landline, and 22 had access to both types of phones.

The chi-square statistic was calculated as 9.73 and has a p-value of 0.0077.Using α=0.01 what can you conclude?

	A.	There is enough evidence that the distribution is different than in 2010.
	B.	There is enough evidence that the distribution is the same as in 2010.
	C.	There is not enough evidence that the distribution is different than in 2010.
	D.	There is not enough evidence the distribution is the same as in 2010.

18. According to the CDC 2.8% of high school students currently use electronic cigarettes. A high school counselor is concerned that the use of e-cigs at her school is higher.

A test of the following hypothesis Ho: p = 0.028 Ha: p > 0.028 is conducted using a random sample of 50 students at this school and the null hypothesis is rejected. What conclusion can the counselor make?

	A.	There is not enough evidence that the percent of students using e-cigs is higher than2.8%.
	B.	There is not enough evidence that the percent of students using e-cigs is 2.8%.
	C.	There is enough evidence that the percent of students using e-cigs is higher than2.8%.
	D.	There is enough evidence that the percent of students using e-cigs is 2.8%.

Answer 1