Question

A and B were supposed to finish a piece of work together in 30 days. They worked together for 20 days and then B left. A finished the remaining work after another 20 days.
How many days would A take to finish the job alone?

• A. 40
• B. 50
• C. 54
• D. 60
• E. 59

Answer 1

The correct option is D

60

(A+B)’s 20 days’ work = $(\frac{1}{30}\times 20)=\frac{2}{3}$

Remaining work = $(1-\frac{2}{3})=\frac{1}{3}$

Now, $\frac{1}{3}$ work is done by A in 20 days.

Whole work will be done by A in $(20\times 3)=60$ days