Find three numbers in G.P. whose sum is 52 and the sum of whose products pairs is 624.

Options

A. 2, 12, 32
B. 2,12, 72
C. 4, 12, 36
D. None of these

Answer

C

Explanation

Let the numbers are `a/r,a and ar.`

Then, `a/r+a+ar = 52`

`=>a(1/r+1+r) = 52->(1)`

Also,

`a/r(a)+a(ar)+a/r(ar) = 624`

`=> a^2(1/r+r+1) = 624->(2)`

`=>a(a(1/r+r+1)) = 624`

Using (1),

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