Question 45662
It takes a pipe 10 minutes less than another one to fill a tank of water. Both pipes together can fill the tank in 12 minutes. How long will it take each one to fill the tank separately?

Faster Pipe DATA:
 Time to do the job = x minutes;  Rate= (1/x) job/min 

Slower Pipe Data:
 Time to do the job = x-10 minutes: Rate = 1/(x-10) job/min

Filling Together Data:
 Time to do the job = 12 minutes: Rate = 1/12 job/min

EQUATION:
 rate + rate = rate together
1/x + 1/(x-10) = 1/12

[x-10+x]/[x(x-10} = 1/12
12(2x-10) = x^2-10x
x^2-34x+120=0
(x-30)(x-4)=0
x= 30 minutes or x= 4 minutes
Only the x=30 minute answer applies because the slower pipe time is then 20 min.
Slower pipe time is 30 minutes.
Faster pipe time is 20 minutes.
Cheers,
Stan H.