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Question
The numbers 3, x, and x + 6 form are in G.P. Find 20th term.
Solution
r = `6/3` = 2 or r = `(-3)/3` = – 1
tn = arn–1
∴ t20 = 3(219) or t20 = 3(– 1)19
∴ t20 = 3(219) or t20 = – 3
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