Question

A can do a work in 20 days and b can do the same work in 30 days. In how many days can a and b together do the work ?

Answer 1

Answer:

1/20+1/30= 30+20/60

=50/60=5/6 days

Answer 2

Answer :-

12 days are required.

Given :-

(i) Number of days required to complete work by A = 20days

(ii) Number of days required to complete work by B = 30days

To find :-

Days required to complete work when they work together ???

Solution :-

Total work = L.C.M (20,30)

= 60

Efficiency of A = 60/20

= 3

Similarly :-

For B = 60/30 = 2

Now,

Total time taken if A and B when they work together = 60/5 = 12 days.