A can complete 2/3rd of work in 10 days and B can complete 4/5th work in 8 days. They work together for 5 days. The remaining work is completed by C alone in 6 days. In how many days C alone can complete 75% of the same work?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 27
A can complete 2/3rd of work in 10 days
So, A completed a work = 10 × 3/2 = 15 days
B can complete 4/5th work in 8 days.
So, B completed the work = 8 × 5/4 = 10 days
Total work = LCM of 15 and 10 = 30 unit
Efficiency of A = 30/15 = 2 unit/day
Efficiency of B = 30/10 = 3 unit/ day
A and B's 5 days work = (2 + 3) × 5 = 25
Remaining work done by C in 6 days.
So, the efficiency of C = (30 - 25)/C = 6
Efficiency of C = 5/6
ATQ, Total days if C alone finish the 75% of the work = = 27 days