A is thrice as good a work man as B and takes 10 days less to do a piece of…
2024
A is thrice as good a work man as B and takes 10 days less to do a piece of work than B takes. B can do the work in how many days ?
- A.
12
- B.
15
- C.
18
- D.
20
Attempted by 819 students.
Show answer & explanation
Correct answer: B
Solution: Use rates (efficiencies) and the inverse relation between rate and time.
Let B take x days to complete the work.
A is thrice as good as B, so A's work rate = 3 × B's rate. Therefore A takes x/3 days.
Given A takes 10 days less than B: x − x/3 = 10.
Solve: (2/3)x = 10 ⇒ x = 10 × (3/2) = 15 days.
Therefore B can do the work in 15 days.