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The flow of water through a drainage pipe was monitored for a 3-hour period. In the second hour, the rate of flow was 15 gallons per hour, which was 50 percent faster than the rate of flow for the first hour. If 25 percent more water flowed through the pipe in the third hour than it did in the second, how many gallons of water flowed through the pipe during the entire three hours?
A. 41.25
B. 42.5
C. 43.75
D. 45.0
E. 57.5
Let x be the rate of flow for the first hour. Since in second hour the rate is 1/2 faster than in the first hour it would be (3/2)*x(=x+ (1/2)*x).
So (3/2)*x=15 ---> x=10 gallons per hour.
Similarly in the third hour it would be (15+(1/4)*15)=18.75 gallons per hour.
The total gallons of water flowed through the pipe during the entire three hours, therefore, is 43.75(=10 + 15+18.75) gallons.
The answer is (C).
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