A can do a piece of work in 18 days and the efficiency of B and C is 15 unit/day and 13 unit/day respectively. Work done by A and C together in 1 day is 3 units more than B and C together. Then find the time taken by B is how much percent more than time taken by A ?
Answer & explanation
Correct answer: option 2
B C
Efficiency 15 13
ATQ,
(A+C) - (B+C) = 3
A - B = 3 (A's eff. is 3 unit more than B's)
Efficiency of A = 15 + 3 = 18
Hence,
A B
efficiency 18 15
Time taken by A & B 15 18
Total work = Efficiency × Number of days
So ratio of efficiency and time is inverse to each other
Now, more time is taken by B i.e 3R
Required % = \(\frac{3R}{15R}\) × 100 = 20%