Question

A & b together can do a work in 12 days, b & c do the same work in 18 days, a & c can complete it in 20 days. in how many days a alone can complete the work?

Answer 1

A+b=12
B+c=18
C+a=20
2(a+b+c)=50
A+b+c=25
Now c=13
A=7
B=30