Scott's average (arithmetic mean) golf score on his first four rounds was 18.What score does he need on his fifth round to drop his average score by 2 points?
Options:
(A) 68
(B) 72
(C) 8
(D) 88
(E) 312
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Average score for first 4 rounds = 18
Average score after 5 rounds = 16
Score Scott needs on his 5th round to drop average score by 2 points = 18 - (2*5) = 8 So the answer is: (C).
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In each series, look for the degree and direction of change between the numbers. In other words, do the numbers increase or decrease, and by how much? Look at this series: 5, 43, 15, 33, 25, ...What number should come next?
Options:
(A) 10
(B) 40
(C) 23
(D) 13
(E) 20
--
C
23
This is an alternating addition and subtraction series. In the first pattern, 10 is added to each number to arrive at the next. In the second, 10 is subtracted from each number to arrive at the next. So the answer is: (C).
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The average of first six prime numbers greater than 20 is?
Options:
(A) 10
(B) 20
(C) 30
(D) 40
(E) 34
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23 + 29 + 31 + 37 + 41 + 43 = 204/6 = 34 So the answer is: (E).
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