Three people A, B and C worked together and finished the work in 9 days. If A alone can finish the same work in 18 days, B alone in 30 days, then the number of days C alone will take is:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 3 i.e. 45 days.
Total work = LCM of 9, 18, and 30 = 90
Efficiency of C = (90/9) - (90/18) - (90/30) = 10 - 5 - 3 = 2
Time required for C alone = 90/2 = 45 days