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The arithmetic mean and geometric mean of two positive numbers are 10 and 8 respectively. The numbers are:
A10 and 8
B16 and 4
C12 and 8
D18 and 2
Answer & Solution
Correct answer: B. 16 and 4
a+b = 2·A.M. = 20 and ab = (G.M.)² = 64. The numbers are roots of x²−20x+64=0 ⟹ 16 and 4.
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