Question

A can do a piece of work in 4 hours; B and C can do it in 3 hours. A and C can do it in 2 hours. How long will B alone take to do it? 

(a) 10 hours 

(b) 12 hours 

(c) 8 hours 

(d) 24 hours

Answer 1

Correct option (b) 12 hours

Explanation:

If (A+C)'s one day work = 6 units 

And A's one day work = 3 units then 

C’s one day work = 6 – 3=3 units. 

(B+C)'s one day work = 4 units then 

B's one day work = 1 unit B can complete the whole work in