JEE Main 2020 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 9 January 2020, Shift 2, Maths Q57

Question 57 of 75 in this shift, Maths question 7 of 25, Section A.

Let

a_n

be the

n^{\mathrm{th}}

term of a G.P. of positive terms. If

\sum_{n=1}^{100}a_{2n+1}=200

and

\sum_{n=1}^{100}a_{2n}=100

, then

\sum_{n=1}^{200}a_n

is equal to :

(1) $300$
(2) $150$ Official answer
(3) $175$
(4) $225$

Official answer

Option 2

NTA final key (Jan 2020).

Chapter: Sequences and Series
Topic: AP and GP
Idea tested: GP Sum of n terms

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Asked 5× in all

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.