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Question -

Insert 5 geometric means between 32/9 and 81/2.



Answer -

Let the five terms bea1, a2, a3, a4, a5.

A = 32/9, B = 81/2

Now, these 5terms are between A and B.

So the GP is: A, a1,a2, a3, a4, a5, B.

So we now have 7 termsin GP with the first term being 32/9 and seventh being 81/2.

We know that, Tn =arn–1

Here, Tn = 81/2,a = 32/9 and

81/2 = 32/9r7-1

(81×9)/(2×32) = r6

r = 3/2

a1 =Ar = (32/9)×3/2 = 16/3

a2 =Ar2 = (32/9)×9/4 = 8

a3 =Ar3 = (32/9)×27/8 = 12

a4 =Ar4 = (32/9)×81/16 = 18

a5 =Ar5 = (32/9)×243/32 = 27

 The five GMbetween 32/9 and 81/2 are 16/3, 8, 12, 18, 27

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