x does a work in 20 days . y does the same work in 40 days . in how many days they together will do the same work ?
x ' s 1 day ' s work = 1 / 20 y ' s 1 day ' s work = 1 / 40 ( x + y ) ' s 1 day ' s work = ( 1 / 20 + 1 / 40 ) = 1 / 13.33 both together will finish the work in 13.33 days . correct option is e
inverse(add(divide(const_1, 20), divide(const_1, 40)))