A and B together can do a piece of work in 30 days.A having worked for 16 days, B finishes the remaining work in 44 days. In how many days shall B finish the whole work alone?

A.  30 days   
B.  40 days
C.  60 days   
D.  70 days
Answer:     C

Explanation :

A's 1 day's work    = x
B's 1 day's work    = y
Then, x+y = 1/30 and 16x+44y = 1.
Solving these two equations, we get x=1/10 and y=1/60
Therefore B's 1 day's work= 1/60.