Question

Water flows back and forth between a small and large tank. When water is moving into a tank the flow rate is positive, and when water is moving from a tank the flow rate is negative. Each tank begins with 250 gallons of water. The flow rate for the large tank is recorded as –6 gallons per minute. After a period of 25 minutes, which integer represents the amount of water left in the large tank? –400 –100 100 400

Answer 1

100

Explanation:

The volume in the large tank is ...

250 -6t . . . . gallons

At t = 25 minutes, it is ...

250 -6·25 = 250 -150 = 100 . . . . gallons

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Comment on answer choices

The quantity in the tank cannot be negative.