A can do 50% more work as B can do in the same time.
A can do 50% more work as B can do in the same time. B alone can do a piece of work in 20 hours. A, with help of B, can finish the same work in how many hours ?
Answer/Solution
8
Steps/Work
B alone can do a work in 20 hours.
∴ A alone can do 3⁄2 of the work in 20 hours.
i.e., A alone can do the same work in 40⁄3 hours
∴ (A + B)’s one hour’s work = 3⁄40 + 1⁄20 = 5⁄40 = 1⁄8
⇒ A and B together can finish the whole work in 8 hours.
Answer B
∴ A alone can do 3⁄2 of the work in 20 hours.
i.e., A alone can do the same work in 40⁄3 hours
∴ (A + B)’s one hour’s work = 3⁄40 + 1⁄20 = 5⁄40 = 1⁄8
⇒ A and B together can finish the whole work in 8 hours.
Answer B