Question

A and B together can do a piece of work in $6\frac{2}{3}$ days , but B alone can do it in $10$ days. How long will A take to do it alone ?

• A. $12$ days
• B. $20$ days
• C. $25$ days
• D. $28$ days

Answer 1

Answer: (B)

$20$ days

A and B together can do a piece of work in $6\frac{2}{3}\left(\frac{20}{3}\right)$ days
(A+B)'s $1$ day's work$=\frac{3}{20}$

B's $1$ day's work$=\frac{1}{10}$

A's $1$ day's work$=\frac{3}{20}-\frac{1}{10}=\frac{1}{20}$.

Hence, A can finish the work in $20$ days .