The flow of water through a drainage pipe was monitored for a 3-hour period. In the second hour, the rate of flow was 12 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) 31.25
(B) 31.5
(C) 33.75
(D) 35.0
(E) 37.5
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Rate of flow of water in second hour = 12 gallons per hour
Rate of flow of water in first hour = 12/(3/2) = 8 gallons per hour
Rate of flow of water in third hour = (125/100)* 12 = (5/4) * 12 = 15 gallons per hour
Number of gallons of water that flowed through the pipe during the entire 3 hours = 12+8+15 = 35 gallons So the answer is: (D).
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All of the bonds on a certain exchange are designated by a 3-letter, a 4-letter, or a 5-letter code that is created by using the 26 letters of the alphabet. Which of the following gives the maximum number of different bonds that can be designate with these codes?
Options:
(A) 26(26^3 + 26^4)
(B) 26(26^3 + 26^5)
(C) 27(26^3 + 26^5)
(D) 27(26^3) + 26^5
(E) 26^3 + 27(26^5)
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3-letter codes = 26^3;
4-letter codes = 26^4;
5-letter codes = 26^5;
Total = 26^3 + 26^4 + 26^5 = 26^3(1+26) + 26^5 = 26^3*27 + 26^5. So the answer is: (D).
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Find a a prime number from below options?
Options:
(A) 84
(B) 97
(C) 98
(D) 100
(E) 102
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Clearly, 97 is a prime number. So the answer is: (B).
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