(N + 18) persons, each working for 7.5 hours a day, can complete 48% of a work in 20 days. (N + 12) persons can complete the remaining work in 30 days if each of them works for 6.5 hours per day. Determine the value of N.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 18.
Given:
(N + 18) persons, each working for 7.5 hours a day, can complete 48% of a work in 20 days.
(N + 12) persons can complete the remaining work in 30 days if each of them works for 6.5 hours per day
Concept used:
(Man × Days × Hours)/work = constant
Calculation:
⇒ (N + 18) × 7.5 × 20/48 = (N + 12) × 30 × 6.5/52
⇒ 7800N + 140400 = 9360N + 112320
⇒ 9360N - 7800N = 140400 - 112320
⇒ 1560N = 28080
⇒ N = 28080/1560
⇒ N = 18