JEE MATHEMATICS MCQ: SEQUENCE OF SERIES

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Analyzing +4 | -1

Let the sum of an infinite G.P., whose first term is a and the common ratio is

r

, be 5 . Let the sum of its first five terms be

\frac{98}{25}

. Then the sum of the first 21 terms of an AP, whose first term is

10 \mathrm{ar}, n^{\text {th }}

term is

a_n

and the common difference is

10 ar^2

, is equal to

View answer and explanation

Correct option: A

21 a_{11}

Option A (

21 a_{11}

) is correct because after solving for the common ratio and substituting into the sum of the AP, the result simplifies to

21 a_{11}

More Questions from SEQUENCE OF SERIES

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A=\{1,2,3\}, B=\{3,4\}, C=\{4,5,6\}

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a,b,c

a,x,b

b,y,c

{x^2},{b^2},{y^2}

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y

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y=x-2

\sum\limits_{{i=0}}^{2012} a_i

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\log \left(\frac{a}{3 b}\right)

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a, b, c

\frac{3}{4}