X and Y together can finish a piece of work in 15 days, while Y alone can finish it in 40 days. X alone can finish the work in:
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e 24 days
|
Understanding |
Application |
|
1/(Days taken by X alone) + 1/(Days taken by Y alone) = 1/(Days taken by X & Y together)
|
1/X + 1/Y = 1/(X+Y) 1/X + 1/40 = 1/15 1/X = 1/15 - 1/40 1/X = (8-3)/120 1/X = 5/120 1/X = 1/24 X= 24 days |