If 4 men or 6 boys can finish a piece of work in 20 days, then in how many days can 6 men and 11 boys finish the same work?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 6.
Given that
If 4 men or 6 boys can finish a piece of work in 20 days
Let the efficiency of a man and a boy be M and B respectively
6 men and 11 boys finish the same work in D days
Concept used
Work = time × efficiency
According to the question
4M × 20 = 6B = 20
M/B = 3/2
Total work = 4 × 3 × 20 = 240
Hence, the required time D = 240/(6 × 3 + 11 × 2) = 240/(18 + 22) = 240/40 = 6 days