a can do a piece of work in 12 days and b alone can do it in 10 days . b works at it for 5 days and then leaves . a alone can finish the remaining work in
"explanation : b ' s 5 days work = 1 / 10 ∗ 5 = 1 / 2 remaining work = 1 − 1 / 2 = 1 / 2 a can finish work = 12 ∗ 1 / 2 = 6 days option b"
divide(const_1, add(divide(const_1, 12), divide(const_1, 10)))