Question:
Tick (✓) the correct answer:
A can do a piece of work in 15 days. B is 50% more efficient than A. A can finish it in
(a) 10 days
(b) $7 \frac{1}{2}$ days
(c) 12 days
(d) $10 \frac{1}{2}$ days
Solution:
(a) 10 days
Work done by $\mathrm{A}$ in 1 day $=\frac{1}{15}$
$\mathrm{B}$ is $50 \%$ more efficient than $\mathrm{A}$.
$\therefore$ Work done by B in 1 day $=\frac{150}{100} \times \frac{1}{15}=\frac{1}{10}$
Thus, B can complete the work in 10 days.