Question 1099899
<br>Here is an alternative method of solution for this kind of problem which avoids working with fractions....<br>
Consider the 60 minutes it takes the third pipe to fill the tank.<br>
The first pipe could fill 3 of the tanks in those same 60 minutes.
The second pipe could fill 2 of the tanks in the 60 minutes.<br>
So all working together, the three pipes could fill 1+3+2 = 6 tanks in 60 minutes.<br>
And that means they could fill the one tank in 10 minutes.