JEE Main 2023 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 8 April 2023, Shift 1, Maths Q8

Question 8 of 90 in this shift, Maths question 8 of 30, Section A.

If the coefficients of three consecutive terms in the expansion of

(1+x)^n

are in the ratio

1:5:20

, then the coefficient of the fourth term is

(1) $1827$
(2) $3654$ Official answer
(3) $5481$
(4) $2436$

Official answer

Option 2

NTA final key.

Chapter: Binomial Theorem
Topic: Binomial Coefficients
Idea tested: Ratio of Consecutive Coefficients

Same idea in other shifts

Asked 9× 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 108 of the 174 JEE Main shifts held from 2017 to 2026.