Question

Rini is twice as good as Vinay. Together, they finish the work in 14 days. In how many days can Vinay alone do the same work?

• A. 16 days
• B. 21 days
• C. 32 days
• D. 42 days

Answer 1

The correct option is D 42 days

Rini being twice as good as Vinay, If the efficiency of Rini is $\frac{1}{R}$ then the efficiency of Vinay $=\frac{1}{2R}$
Together they can finish the work in 14 days. So the amount of work done in 1 day $=\left(\frac{1}{R}\right)+\left(\frac{1}{2R}\right)=\frac{1}{14}$
Solving, R $=21$ days.
Therefore time taken by Vinay to complete the work alone $=2\times 21=42$ days.