a can do a job in 18 days and b can do it in 30 days . a and b working together will finish thrice the amount of work in - - - - - - - days ?
"explanation : 1 / 18 + 1 / 30 = 8 / 90 = 4 / 45 45 / 4 = 45 / 4 * 3 = 33 3 / 4 days answer : c"
add(divide(const_1, 18), divide(const_1, 30))