a , b and c can complete a piece of work in 24 , 6 and 12 days respectively . working together , they will complete the same work in :
if a can do a piece of work in n days , then a ' s 1 day ' s work = 1 / n ( a + b + c ) ' s 1 day ' s work = 1 / 24 + 1 / 6 + 1 / 12 = 7 / 24 so , all the three together will complete the job in = 24 / 7 days answer : c
inverse(add(inverse(12), add(inverse(24), inverse(6))))