Question

A bathtub contains 20 gallons of water. After the drain is opened, there are 14 gallons of water remaining after 30 seconds. Using this information, how can you describe the rate of change in the amount of water remaining in the tub per second?

a decrease of 0.5 gallons per second


an increase of 0.5 gallons per second


a decrease of 0.2 gallons per second


an increase of 0.2 gallons per second

Answer 1

a decrease of 0.2 gallons per second

Step-by-step explanation

The drain was open for 30 seconds.

The water that ran out for 30 seconds = 20 - 14

= 6 gallons

Rate of decrease = (change in gallons)/(time taken)

= 6/30

= 0.2

The rate of change in the amount of water remaining in the tub per second will be the same as the one that ran out since the outlet is the same.

So the correct answer from the choices is "a decrease of 0.2 gallons per second".