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Re: The arithmetic mean (average) of the numbers a and b is 17. [#permalink]
1
Theory

    ➡ Arithmetic Mean or Average = Sum of all the Values / Total Number of Values
    ➡ Geometric Mean = \(n\sqrt{x_1 * x_2 * x_3 ...* x_n}\)

The arithmetic mean (average) of the numbers a and b is 17

Arithmetic Mean = \(\frac{Sum}{2}\) = \(\frac{a + b }{2}\) = 17 (given)
=> a + b = 17*2 = 34
=> a = (34-b) ...(1)

The geometric mean of the numbers a and b is 8

Geometric Mean = \(\sqrt{a*b}\) = 8 (given)
Squaring both the sides we get

a*b = 8*8 = 64
Substituting the value of a from (1) we get
(34-b)*b = 64
=> \(b^2\) - 34b + 64 = 0
=> \(b^2\) - 2b - 32b + 64 = 0
=> b* (b-2) - 32*(b-2) = 0
=> (b-2) * (b-32) = 0
=> b = 2, 32
=> a = 34 - b = (34-2) or (34-32) = 32 or 2

But we cannot find a unique value of a nd b they can be (2,32) or (32,2) respectively

So, Answer will be D.
Hope it helps!

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Re: The arithmetic mean (average) of the numbers a and b is 17. [#permalink]
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