Question

A takes twice as much time as b or thrice as much time as c to finish a piece of work. working together, they can finish the work in 2 days. b can do the work alone in:
a. 4 days
b. 6 days
c. 8 days
d. 12 days

Answer 1

let A take 6x days..
B take 3x days and C take 2x days to complete the work....
so, 1/x+1/2x+1/3x=1/2
3/2x+1/3x=1/2
9x/6x^2=1/2
3/2x=1/2
3=1/2*2x
so x=3
and B=3x=9 days to complete the work...