Question

A can finish a work in $18$ days and B can do the same work in $15$ days. B worked for $10$ days and left the job. In how many days, A alone can finish the remaining work?

• A. $5$ days
• B. $\frac{11}{2}$ days
• C. $6$ days
• D. $8$ days

Answer 1

The correct option is C $6$ days

A can finish the work in $18$ days
Work rate of A $=\frac{100}{18}=5.55\%$ pr day
B can complete the work in $15$ days
Work rate of B $=\frac{100}{15}=6.66\%$ per day
Work done by B in 10 days $=6.66\%\times 10=66.6\%$
Work left $=100-66.6=33.33\%$
So, A will complete this work in,'
$\frac{33.33}{5.55}=6$ days