Time and Work Practice Test 3 with solutions

Number of days taken by Bharat to complete the work = $15\times \frac{4}{3}$ = 20 days
Number of days taken by Bhaskar to complete the work = 7 × 2 = 14 days.
Work done by Bharat in one day = $\frac{1}{20}$
Work done by Bhaskar in one day = $\frac{1}{14}$
Work done by both in one day = $\frac{1}{20}+\frac{1}{14}$
= $\frac{7+10}{140}$ = $\frac{17}{140}$
So, number of days taken by both together to complete the work
= $\frac{140}{17}$ = $8\frac{4}{17}$ days