Question

A and B can do a piece of work in 12 days whereas B and C can do it in 15 days. If all
the three work together, it can be linished in 10 days. How long will it take for A and C to
do it together?
M ENTERET
Mariram is thrice as good a workman as Kamal and takes 10 day less than Kamal to
dieses​

Answer 1

Answer:

LCM of 12,15,10 = 60

efficiency = 5,4,6 (A+B,B+C, A+B+C)

so,

efficiency of C = (A+B+C) - (A+B) = 6-5 = 1

efficiency of A = (A+B+C) - (B+C) = 6-4 = 2

so,

efficiency of A+C = 1+2 = 3

Time they will take = 60/3 = 20 days (Ans)