Instruction 2.9
A sample of 200 students at a large university was taken after the final exam to ask them whether they went out on the weekend before the exam or spent the weekend studying, and whether they did well or poorly on the exam. The following table contains the result.
$$\begin{array} { | l | l | l | }
\hline & \text { Did Well on Exam } & \text { Did Poorly on Exam } \
\hline \text { Studying for Exam } & 80 & 20 \
\hline \text { Went out on the weekend } & 30 & 70 \
\hline
\end{array}$$
-Referring to Instruction 2.9,if the sample is a good representation of the population,we can expect _________% of those who spent the weekend studying to do poorly on the exam.
A) 20
B) 10
C) 50
D) 45

Question

Instruction 2.9
A sample of 200 students at a large university was taken after the final exam to ask them whether they went out on the weekend before the exam or spent the weekend studying, and whether they did well or poorly on the exam. The following table contains the result.
 $$\begin{array} { | l | l | l | } 
\hline & \text { Did Well on Exam } & \text { Did Poorly on Exam } \
\hline \text { Studying for Exam } & 80 & 20 \
\hline \text { Went out on the weekend } & 30 & 70 \
\hline
\end{array}$$
-Referring to Instruction 2.9,if the sample is a good representation of the population,we can expect _________% of those who spent the weekend studying to do poorly on the exam.
A) 20
B) 10
C) 50
D) 45

Quizplus · Accepted Answer

20% of those who spent the weekend studying did poorly on the exam, as shown by the 20 out of 100 (80 did well + 20 did poorly = 100 who studied).

Instruction 2 -Referring to Instruction 2