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,_________ %t of the students in the sample spent the weekend studying and did well on the exam.
A) 40
B) 50
C) 80
D) 72.72

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,_________ %t of the students in the sample spent the weekend studying and did well on the exam.
A) 40
B) 50
C) 80
D) 72.72

Quizplus · Accepted Answer

40The percentage of students who spent the weekend studying and did well on the exam is calculated by dividing the number of students who studied and did well (80) by the total number of students in the sample (200) and then multiplying by 100 to get the percentage: $\frac{80}{200} \times 100 = 40\%$.

Instruction 2 -Referring to Instruction 2