The bar chart represents the distribution of marks scored by students in an economics examination. Use the bar chart to answer questions 30 to 32

If the failed mark was 4, what is the probability that a student selected at random passed?

The bar chart represents the distribution of marks scored by students in an economics examination. Use the bar chart to answer questions 30 to 32

If the failed mark was 4, what is the probability that a student selected at random passed?

A.

0.36

B.

0.74

C.

0.52

D.

0.64

Correct answer is D

Total number of students = total frequency = 3 + 6 + 9 + 1 + 12 + 7 + 5 + 10 = 53
Since the failed mark was 4,
Total number of students that passed = 12 + 7 + 5 + 10 = 34

Pr( passed) = \(\frac{34}{53}\) = 0. 64