JEE Main 2020 · MathsNumerical answerNumerical valueMediumCalculation

JEE Main 9 January 2020, Shift 2, Maths Q71

Question 71 of 75 in this shift, Maths question 21 of 25, Section B.

C_r\equiv{}^{25}C_r

and

C_0+5\cdot C_1+9\cdot C_2+\ldots+(101)\cdot C_{25}=2^{25}\cdot k

, then

k

is equal to ______.

Official answer

51.00

NTA final key (Jan 2020).

Chapter: Binomial Theorem
Topic: Binomial Coefficients
Idea tested: Differentiation Method for Sums

Same topic in other shifts

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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.