Question

katherine bought two hoses. the second hose will fill up an oil tank twenty percent slower than the first. if katherine uses both hoses to fill up and oil tank, it will take 16 4/11 minutes. how long will it take if katherine only uses the second hose?

Answer 1

Let x = rate of first hose.
.8x = rate of second hose (it is 20% slower) so it is 80% of the first hose rate.
With both hoses the rate would be 1.8 x which completes the job in 16 4/11 minutes.
multiplying the rate by time shows the capacity of the oil tank as 29.45
to accomplish with the second hose along would be 29.45/.8=36.8 minutes.

That doesn't seem to just right, but you might get some ideas from it.

Answer 2

that seems about right! thank you :D