A man is twice as fast as a woman and a woman is twice as fast as a boy in doing a work. If all of them a man, a woman and a boy can finish a piece of work in 7 days, then in how many days a boy will do it alone?
Answer & explanation
Correct answer: option 1
ATQ, Efficiency ratio:
Man : Women : Boy = 4 : 2 : 1 = 7R (total)
Total Work = Efficiency × time = 7 × 7 = 49
The boy alone will do it in = \(\frac{49}{1}\) = 49 days