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Question
Which term of the G.P. 5, 25, 125, 625, … is 510?
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Solution
Let nth term, i.e., tn be 510.
∴ tn = 510
∴ arn–1 = `1/(5^10)`, where a = 5, r = 5
∴ 5.(5)n–1 = 510
∴ 5n = 510
∴ n = 10
Hence, t10 of the G.P. is 510.
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