A & B together earn ₹840 for a job. A works the whole time; B joins after the job is 25% done. B is twice as efficient as A. Find B's share.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. ₹420.
Let A’s rate = 1 unit/day and B’s rate = 2 units/day
Work = 100 units
A alone does 25 units in 25 days.
Remaining 75 units done by A and B together at 3 units/day ⇒ 75/3 = 25 days
So A works 50 days, B works 25 days.
Work done A = 50 × 1 = 50 units, B = 25 × 2 = 50 units
Work ratio of A and B = 1 : 1 [Equal share]
B's share = 840/2 = 420