This page offers a step-by-step solution to the specific question **NCERT Class 11th Mathematics - Sequence and Series | given a g p with nbsp a nbsp 729 and 7th nbsp t Answer ** from NCERT Class 11th Mathematics, Chapter Sequence and Series.

Question 15

Given a G.P. with *a* = 729 and 7th term 64, determine S_{7}.

Answer

*a* = 729

*a*_{7} = 64

Let *r* be the common ratio of the G.P.

It is known that, *a*_{n} = *a r*^{n–1}

*a*_{7} = *ar*^{7–1} = (729)*r*^{6}

⇒ 64 = 729 *r*^{6}

^{}

Also, it is known that,

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Mithun
2018-07-16 08:17:35

It was helpful.thank you

Prashant
2018-06-22 23:55:40

Too much helpful. ...

Chandradeep
2017-09-16 20:46:18

Thanks a lot to Saral study who help us better pratice in math

Dhruv
2016-11-11 17:35:17

Thanks for solution. ...

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