Question

A can do a certain job in $12$ days. B is $60\%$ more efficient then A. Find the number of days take by B to finish the job.

Answer 1

According to the question, $A$ can do a job in $12$ days, which means $A$ can do one-twelfth of total work in one day.

So, $A^{\prime }s$ one day work is equal $\frac{1}{12}$

$B$ is $60\%$ more efficient than $A.$

So, $B$ can do $60\%$ more work than what $A$ does in one day.

$B^{\prime }S$ one day work is equal to $\frac{1}{12}+60$%

i.e., $\frac{1}{12}+\frac{1}{20}$, which is $60.$

$\Rightarrow \frac{5}{60}+\frac{3}{60}=\frac{8}{60}\Rightarrow \frac{1}{7.5}$

So, $B$ can do the same work in $7.5$ days or $7$ days and $12$ hours.