Linear Equation word problem help

[jesusfreakmir]

I need help with a Linear Equation word problem. Here it is:
One pipe can be used to fill a tank in 48min. and another can be used to fill it in one hour and 12 min. How long will it take to fill the tank if both pipes are used? I just don't know where to start with this problem so I have no work.

 

[Deleted member 4993]

I need help with a Linear Equation word problem. Here it is:
One pipe can be used to fill a tank in 48min. and another can be used to fill it in one hour and 12 min. How long will it take to fill the tank if both pipes are used?

What fraction of tank is filled in 1 hour by the first pipe?

What fraction of tank is filled in 1 hour by the second pipe?

What fraction of tank is filled in 1 hour by the first and the second pipes together?

continue......