Working together, A, B and C can complete a work in 36 days. If the efficiency of A, B and C are in the ratio 5: 6: 9, then B alone will complete the same work in:
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 120 days.
Efficiency of A, B and C are in the ratio = 5 : 6 : 9.
Work completed by A, B and C = 36 days
Time taken by A to complete the work = x/5
Time taken by B to complete the work = x/6
Time taken by C to complete the work C = x/9
ATQ -
(1/x/5) + (1/x/5) + (1/x/5) = 1/36
(5/x) + (6/x) + (9/x) = 1/36
20/x = 1/36
x = 20 × 36 = 720
Time Taken by B alone to complete the work = 720/6 = 120 days