Question:
Find the 12th term of a G.P. whose 8th term is 192 and the common ratio is 2.
Find the 12th term of a G.P. whose 8th term is 192 and the common ratio is 2.
Updated On: Oct 19, 2023
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Solution and Explanation
Common ratio, r = 2
Let a be the first term of the G.P.
∴ a8 = ar 8–1 = ar7
⇒ ar7 = 192
a(2) 7 = 192
a(2) 7 = (2)6 (3)
⇒a = (2)6 × \(\frac{3}{(2)}7=\frac{3}{2}\)
∴ a12 = ar12 - 1 = \((\frac{3}{2})\)(2)11 = (3)(2)10 = 3072
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