Home » Aptitude » Time and Work

A and B can do a piece of work in 9 days and 18 days, respectively. As they were ill, they could do 90% and 72% of their efficiency, respectively. How many days will they take to complete the work together?

Correct Answer: 71/7

Explanation:

Because of illness,
A's 1 day's work = 90% of 1/9 = 1/10
B's 1 day's work = 72% of 1/18 = 1/25
∴ (A + B)'s 1 day's work
= (1/10) + (1/25) = (5 + 2)/50 = 7/50
Hence, time taken by them to complete the work = 50/7 days
= 71/7


← Previous Question Next Question→

More Questions from Time and Work

Discussion & Comments

No comments yet. Be the first to comment!
Join Discussion