15. A Pew Poll in 2010, found that 50% of adults aged 25-29 hadaccess to only a cell phone, while 40% had access to both acellphone and landline and 10% had access to only a landline. Wewish to conduct a Goodness of Fit Test to see if the results of apoll of a random sample of 130 adults aged 25-29 are significantlydifferent from the 2010 poll results.
The random sample of 130 adults found that 69 had access to onlya cell phone, 39 had access to only a landline, and 22 had accessto both types of phones.
Which of the following are the correct null and alternativehypothesis 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 hadaccess to only a cell phone, while 40% had access to both acellphone and landline and 10% had access to only a landline. Wewish to conduct a Goodness of Fit Test to see if the results of apoll of a random sample of 130 adults aged 25-29 are significantlydifferent from the 2010 poll results. The table below presents theobserved 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 hadaccess to only a cell phone, while 40% had access to both acellphone and landline and 10% had access to only a landline. Wewish to conduct a Goodness of Fit Test to see if the results of apoll of a random sample of 130 adults aged 25-29 are significantlydifferent from the 2010 poll results.
The random sample of 130 adults found that 69 had access to onlya cell phone, 39 had access to only a landline, and 22 had accessto both types of phones.
The chi-square statistic was calculated as 9.73 and has ap-value of 0.0077.Using ?=0.01 what can you conclude?
| A. | There is enough evidence that the distribution is different thanin 2010. |
| B. | There is enough evidence that the distribution is the same as in2010. |
| C. | There is not enough evidence that the distribution is differentthan in 2010. |
| D. | There is not enough evidence the distribution is the same as in2010. |
18. According to the CDC 2.8% of high school students currentlyuse electronic cigarettes. A high school counselor is concernedthat 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 thisschool and the null hypothesis is rejected. What conclusion can thecounselor make?
| A. | There is not enough evidence that the percent of students usinge-cigs is higher than2.8%. |
| B. | There is not enough evidence that the percent of students usinge-cigs is 2.8%. |
| C. | There is enough evidence that the percent of students usinge-cigs is higher than2.8%. |
| D. | There is enough evidence that the percent of students usinge-cigs is 2.8%. |
