A and B can complete a work in 10 and 12 days respectively. A and B start working together and after 3 days, A left the work. Find in how many days work will be completed.
Answer & explanation
Correct answer: option 1
Total work = Efficiency × Number of days
work done by ( A + B ) in 3 days = ( 6R + 5R ) × 3 = 33R
Remaining work = 60R - 33R = 27R
Time taken by B to complete the remaining work = \(\frac{27R}{5R}\)
= \(\frac{27}{5}\)
total time taken in doing whole work = 3 + \(\frac{27}{5}\)
= \(\frac{42}{5}\) = 8\(\frac{2}{5}\)