The ratio of efficiencies of X and Y for doing a certain work is 5 : 9. Working together, they can complete a work in 15 days, X alone will complete 66(2/3)% of the same work in:
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 28 days.
Given:
The ratio of efficiencies of X and Y for doing a certain work is 5 : 9
X and Y can complete the work in 15 days.
Formula used:
Work = efficiency × total time ---- (1)
Calculations:
Total work (LCM of 14 and 15) = 210 units
Work done by X and Y each day = 210/15 = 14 units
Work done by X = 5 units
Work done by Y = 9 units
66(2/3)% of the same work = 210 × 2/3 = 140 units
Required time taken by X = 140/5 = 28 days