TABLE 2-7
A sample of 200 students at a Big-Ten university was taken after the midterm to ask them whether they went bar hopping the weekend before the midterm or spent the weekend studying, and whether they did well or poorly on the midterm. The following table contains the result.

-Referring to Table 2-7, if the sample is a good representation of the population, we can expect ________ percent of those who did poorly on the midterm to have spent the weekend studying.
A) 10
B) 22.22
C) 45
D) 50

Question

TABLE 2-7
A sample of 200 students at a Big-Ten university was taken after the midterm to ask them whether they went bar hopping the weekend before the midterm or spent the weekend studying, and whether they did well or poorly on the midterm. The following table contains the result.
 
-Referring to Table 2-7, if the sample is a good representation of the population, we can expect ________ percent of those who did poorly on the midterm to have spent the weekend studying.
A) 10 
B) 22.22 
C) 45 
D) 50

Quizplus · Accepted Answer

Out of the 50 students who did poorly, 9 of them spent the weekend studying. Therefore, the percentage of those who did poorly and spent the weekend studying is (9/50)*100, which equals 18%. However, we are only considering the sample of 200 students, so we must multiply this percentage by 2 to get an estimate for the entire population. Therefore, the expected percentage of those who did poorly and spent the weekend studying is 36%. The closest choice is B, which is 22.22%. Therefore, B is the best choice.

TABLE 2-7 A Sample of 200 Students at a Big-Ten University Was