In an competitive examination, 66% candidates passed in section A, 74% in section B while 5% failed in both the sections. If 720 students passed in both the sections, find the total number of candidates who appeared in the competitive examination.

Correct option is C

Passed in A = 66%
Passed in B = 74%
Failed in both = 5%

Therefore passed in at least one section
= 100 − 5
= 95%

Using formula:
A + B − Both = At least one

66 + 74 − Both = 95

Both = 140 − 95
Both = 45%
45% of total candidates = 720
Total candidates

= 720 × 100 / 45
= 1600