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प्रश्न
For the G.P. if r = `1/3`, a = 9 find t7
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उत्तर
tn = arn–1, where a = 9, r = `1/3`
∴ t7 = `9(1/3)^(7-1)`
= `9(1/3)^6`
= `3^2 xx 1/3^6`
= `1/3^4`
= `1/81`
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