A, B and C can do a work in 5 days,6 days and 10 days, respectively. Working together, in how many days will they finish the same work?

$2\frac{1}{7}$ $4\frac{1}{7}$ $3\frac{1}{7}$ $1\frac{1}{7}$

$2\frac{1}{7}$

A = 5 days, B = 6 days, c = 10 days,   ⇒ A + B+ C can do the work in = \(\frac{30}{6+5+3}\) = \(\frac{30}{14}\) = \( {2 }_{ 7}^{1 } \) days.    ..(\(\frac{Work}{Efficiency}\) = Time)