Question

Two pumps are filling large vats of liquid. One vat is empty, and the pump is filling it at a rate of 6 gallons per minute. The other is already filled with 10 gallons, and it is continuing to fill at a rate of 4 gallons per minute. Write an equation to show when the two vats will have an equal amount of liquid. Use x as your variable.

Answer 1

Let x be minutes. Amount in first vat: 6x gallons. Amount in second vat: 10 + 4x gallons. Set equal:

6x = 10 + 4x

Solving gives 2x = 10, so x = 5 minutes.