q: The flow of water through a drainage pipe was monitored for a 3-hour period. In the second hour, the rate of flow was 24 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?
Options:
(A) 61.25
(B) 62.5
(C) 63.75
(D) 70.0
(E) 77.5
a: Stream of consciousness: Rate of flow of water in second hour = 24 gallons per hour
Rate of flow of water in first hour = 24/(3/2) = 16 gallons per hour
Rate of flow of water in third hour = (125/100)* 24 = (5/4) * 24 = 30 gallons per hour
Number of gallons of water that flowed through the pipe during the entire 3 hours = 16+24+30 = 70 gallons The answer is (D).
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q: A technician makes a round-trip to and from a certain service center by the same route. If the technician completes the drive to the center and then completes 10 percent of the drive from the center, what percent of the round-trip has the technician completed?
Options:
(A) 5%
(B) 10%
(C) 25%
(D) 40%
(E) 55%
a: Stream of consciousness: Assuming that the technician makes a round-trip of 40 miles (each way is 20 miles), then the technician would have completed 20 miles + 2 miles (10% of the remaining 20 miles). Therefore, the total is 22 miles. 22miles/40 miles is 55% of the entire trip. The answer is (E).
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q: A train 90 meters long is running with a speed of 54 kmph. The time taken by it to cross a tunnel 120 meters long is?
Options:
(A) 29
(B) 18
(C) 14
(D) 99
(E) 13
a:
Stream of consciousness: D = 90 + 120 = 210
S = 54 * 5/18 = 15 mps
T = 210/15 = 14 se The answer is (C).
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