A alone can do a piece of work in 7 days, while B alone can do if in 10 days. In how many days will they complete the same work if they work together?
Answer & explanation
Correct answer: option 3
A = 7 days, B = 10 days,
⇒ Time required for A + B to complete the work = \(\frac{70}{7 + 10}\) = \(\frac{70}{17}\) days. ..(\(\frac{Work}{Efficiency}\) = Time)