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?

$\frac{105}{17}$ days $\frac{35}{17}$ days $\frac{70}{17}$ days $\frac{84}{17}$ days

$\frac{70}{17}$ days

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)