Which of the following is equal to the average (arithmetic mean) of (y+4)^2 and (y-4)^2?
Options:
(A) x^2
(B) x^2+2
(C) x^2 +12
(D) x^2+21
(E) y^2+16
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Avg = [(y+4)^2 + (y-4)^2] / 2
Expanding and simplifying, (y^2 + 8y + 16 + y^2 - 8y + 16 ) / 2 = y^2 + 16 So the answer is: (E).
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Find the value of y from (12)^3 x 6^ 4 ÷ 432 = y?
Options:
(A) 3456
(B) 4567
(C) 4789
(D) 5678
(E) y=5184
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Given Exp. = (12)3 x 64 = (12)3 x 64 = (12)2 x 62 = (72) 2 = 5184
432 12 x 62 So the answer is: (E).
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How much more would Rs.20000 fetch, after two years, if it is put at 20% p.a. compound interest payable half yearly than if is put at 20% p.a. compound interest payable yearly?
Options:
(A) 482
(B) 887
(C) 299
(D) 277
(E) 200
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20000(11/10)4 - 20000(6/5)2 = 482 So the answer is: (A).
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