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Question
The first two terms of a G.P. are 125 and 25 respectively. Find the 5th and the 6th terms of the G.P.
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Solution
First term (a) = 125
And common ratio (r) = `25/125 = 1/5`
Now tn = arn – 1
`=>` 5th term = t5
= `125 xx (1/5)^(5 - 1)`
= `125 xx (1/5)^4`
= `125 xx 1/625`
= `1/5`
`=>` 6th term = t6
= `125 xx (1/5)^(6 - 1)`
= `125 xx (1/5)^5`
= `125 xx 1/3125`
= `1/25`
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