2 taps A and B can fill a bucket in 12 and 18 minutes resp. How long will it take both the taps to fill the bucket.

We can also set up an equation to solve this work
problem.

We are given that tap A can fill a bucket by
itself in 12 minutes and tap B can fill the bucket in 18 minutes.   We are asked how
long it will take for the two taps running together to fill the
bucket.

=> let x = total job time for both working
together

=> let 1/12x  = time it takes for tap A to
fill the bucket

=> let 1/18x = time it takes for tap
B to fill the bucket

=> The entire completion of the
job will be equal to 1

=> 1/12 x + 1/18x = 1
(completed job)

=> 36 [1/12 x + 1/18x = 1]    (to
clear fractions)

=> 3x + 2x =
36

=> 5x = 36

=>
x =36/5 or 7.2 minutes

Both taps running
together will fill the bucket in 7.2 minutes.