A certain car uses 12 gallons of gasoline in traveling 300 miles. In order for the car to travel the same distance using 10 gallons of gasoline, by how many miles per gallon must the car’s gas mileage be increased?
Options:
(A) 2
(B) 4
(C) 5
(D) 8
(E) 10
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300/10 = 30. The difference is 30 - 25 = 5. So the answer is: (C).
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A 70 cm long wire is to be cut into two pieces so that one piece will be 2/5th of the other, how many centimeters will the shorter piece be?
Options:
(A) 20 cm
(B) 15 cm
(C) 30 cm
(D) 40 cm
(E) 45 cm
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1: 2/5 = 5: 2
2/7 * 70 = 20 So the answer is: (A).
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Find the mean proportional between 81 & 100?
Options:
(A) A) 59
(B) B) 61
(C) C) 63
(D) D) 65
(E) E) 90
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Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Formula = √a×b
A = 81 and B = 100
√81×100 = 9 × 10 = 90 So the answer is: (E).
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