JEE Main 2021 · MathsNumerical answerNumerical valueEasyCalculation

JEE Main 25 July 2021, Shift 1, Maths Q83

Question 83 of 90 in this shift, Maths question 23 of 30, Section B.

The ratio of the coefficient of the middle term in the expansion of

(1+x)^{20}

and the sum of the coefficients of two middle terms in expansion of

(1+x)^{19}

is _________.

Official answer

NTA final key.

Chapter: Binomial Theorem
Topic: Binomial Coefficients
Idea tested: Maximum Coefficient for Odd n

Same topic in other shifts

All Binomial Coefficients questions

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4 Apr 2026, Shift 1 · Q9Let the smallest value of $k\in\mathbb{N}$ , for which the coefficient of $x^3$ in…MediumSingle correct
5 Apr 2026, Shift 1 · Q23If the sum of the coefficients of $x^7$ and $x^{14}$ in the expansion of $\left(\frac{1}{x^3} - x^4\right)^n$ , $x \neq 0$ , is zero, then…MediumNumerical value
6 Apr 2026, Shift 1 · Q8If the coefficients of the middle terms in the binomial expansions of $(1+\alpha x)^{26}$ and $(1-\alpha x)^{28}$ , $\alpha\neq 0$ , are…EasySingle correct
8 Apr 2026, Shift 2 · Q8If…HardSingle correct

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.