Question:
If the 5th term of a G.P. is 81 and the 8th term is 6561, the first term is:
If the 5th term of a G.P. is 81 and the 8th term is 6561, the first term is:
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Divide terms to eliminate first term.
Updated On: Jan 5, 2026
- 3
- 9
- 1
- 27
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The Correct Option is B
Solution and Explanation
\[
\frac{T_8}{T_5}=r^3=\frac{6561}{81}=81 \Rightarrow r=3
\]
\[
a=\frac{81}{3^4}=9
\]
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