The third term of G.P. is 4.

Question:

The third term of G.P. is 4. The product of its first 5 terms is

(A) 43 

(B) 44 

(C) 45 

(D) None of these

Solution:

(C) 45

Explanation:

Given the third term of G.P, T3 = 4

To find the product of first five terms

We know that,

Tn = a rn – 1

It is given that, T3 = 4

⇒ ar3 – 1 = 4

⇒ ar2 = 4 … (i)

Product of first 5 terms = a × ar × ar2 × ar3 × ar4

= a5r1+2+3+4

= a5r10

= (ar2)5

= (4)5 [from (i)]

Hence, the correct option is (C)

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