Aptitude Hack#3(26-2-19)

Question:

A can do a work in 15 days and B in 20 days. If they work on it together for 4 days, then the fraction of the work that is left is :

A. 1/4

B. 1/10

C. 7/15

D. 8/15

Answer: D) 8/15

Explanation:

Take LCM of 15, 20 as 60.

A’s 1 day’s work=4.

B’s 1 day’s work=3.

(A+B) 1 day’s work=7.

(A+B) 4 day’s work=28.

Remaining work=60-28=32.

So in Fraction=8/15