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The 5th and 7th terms of a geometric sequence are 12 and 48. What is the 6th term?

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User Magno
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1 Answer

1 vote

Answer:

Explanation:

5th term is 6 and the 7th term is 48, we know the nth term for a GP is arn−1

so let's substitute the given information in that formula for the nth term

ar3=6

ar6=48

ar6ar3=486

The a

and a

cancelout hence we remain with r3=8

take a cube root on both sides and we end up having r=2

Substitute the value of r in any given equation to get the value of a

ar3=6

a(2)3=6

8a=6

a=34

The formula for the nth term of this GP is given by 34(2n−1)

And when you substitute the value of n in the above formula of nth term you will get the following values; 3/4, 3/2, 3, 6…

User Brett Hannah
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