Question

A and b can do a piece of work in 45 and b and c can do it in 10.Days and c and a can do it in 15 days c alone can do it in

Answer 1

(a+b) 1 day work =1÷45
(b+c)1 day work =1÷10
(c+a) 1 day work = 1÷15
2(a+b+c) 1 day wok = 1÷46+1÷10+1÷15
2(a+b+c) 1 day work =17÷90
(a+b+c) 1 day work = 17÷90×1÷2
(a+b+c) 1 day work =17÷180
so c's 1 day work =17÷180-1÷45=13÷180
so c can do it alone in 180÷13 days