SOLUTION: tap A can fill the tank in 6 minutes and tap B in 3 minutes. how long will both tapes take to fill the tank if opened at the same time

Algebra ->  Rate-of-work-word-problems -> SOLUTION: tap A can fill the tank in 6 minutes and tap B in 3 minutes. how long will both tapes take to fill the tank if opened at the same time       Log On


   

Question 1035580: tap A can fill the tank in 6 minutes and tap B in 3 minutes. how long will both tapes take to fill the tank if opened at the same time
Found 2 solutions by ikleyn, Alan3354:
Answer by ikleyn(52788) About Me  (Show Source):
You can put this solution on YOUR website!
.
Tap A can fill the tank in 6 minutes and tap B in 3 minutes. how long will both tapes take to fill the tank if opened at the same time.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 

Tap A fills  1%2F6  of the tank volume in one minute when works alone. Its rate is  1%2F6  of the tank volume per minute.

Tap B fills  1%2F3  of the tank volume in one minute when works alone. Its rate is  1%2F6 of the tank volume per minute.

When both taps work together, they fill  1%2F6+%2B+1%2F3  of the tank volume per minute.
In other words, their combined rate is the sum of their individual rates  1%2F6+%2B+1%2F3 = 1%2F6+%2B+2%2F6 = 3%2F6 = 1%2F2.

It means that two taps fill  1%2F2  of the tank volume per minutes.

Now it is clear that it takes 2 minutes for both taps to fill the tank.

Answer.  It will take 2 minutes for both taps to fill the tank.

The problem is solved.

You can find many other similar solved joint-work problems in the lessons
    - Using Fractions to solve word problems on joint work,
    - Solving more complicated word problems on joint work,
    - Selected joint-work word problems from the archive
in this site.

Read them and become an expert in solving joint-work word problems.


Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
2 minutes.
3*6/(3+6) = 2