The 4^th term of a G.P. is 16 and the 7^th term is 128, then its common ratio is equal to :
2
-2
1
-1
AP GP
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Question

The 4^th term of a G.P. is 16 and the 7^th term is 128, then its common ratio is equal to : 1. 2 2. -2 3. 1 4. -1

KnowledgeBoat · Accepted Answer

Let first term of G.P. be a and common ratio be r. By formula, ⇒ a_n = ar^{n - 1} Given, 4^th term of a G.P. is 16. ⇒ a₄ = 16 ⇒ ar^{4 - 1} = 16 ⇒ ar³ = 16 .........(1) Given, 7^th term of a G.P. is 128. ⇒ a₇ = 128 ⇒ ar^{7 - 1} = 128 ⇒ ar⁶ = 128 .........(2) Dividing equation (2) by (1), we get : Hence, Option 1 is the correct option.

Mathematics

The 4^th term of a G.P. is 16 and the 7^th term is 128, then its common ratio is equal to :
2
-2
1
-1

AP GP

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The 4th term of a G.P. is 16 and the 7th term is 128, then its common ratio is equal to :2-21-1

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The 4^th term of a G.P. is 16 and the 7^th term is 128, then its common ratio is equal to :
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If the first term of a G.P. is 8 and its common ratio is -2. The 3^rd term of this G.P. is :
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