Question

If sachin takes $10$ days to complete a work and Rohan takes $15$ days to complete the same work .How many days it will take if both does the same work together ?

Answer 1

Time taken by Sachin to complete a work $=10$ days

So, work done by Sachin in one day $=\frac{1}{10}$

Time taken by Rohan to complete a work $=15$ days

So, work done by Rohan in one day $=\frac{1}{15}$

Now, work done by Rohan and Sachin together in one day $=\frac{1}{10}+\frac{1}{15}$

$=\frac{5}{30}$

$=\frac{1}{6}$

So, $\frac{1}{6}$ of the work is done by both in $=1$ day

Complete work is done by both in $=1\times \frac{6}{1}=6$ days