x does a work in 30 days . y does the same work in 45 days . in how many days they together will do the same work ?
"x ' s 1 day ' s work = 1 / 30 y ' s 1 day ' s work = 1 / 45 ( x + y ) ' s 1 day ' s work = ( 1 / 30 + 1 / 45 ) = 1 / 18 both together will finish the work in 18 days . correct option is a"
inverse(add(divide(const_1, 30), divide(const_1, 45)))