JEE Main 2025 · MathsMultiple choiceSingle correctHardMulti-step

JEE Main 2 April 2025, Shift 2, Maths Q7

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

\sum_{r=0}^{10}\left(\frac{10^{r+1}-1}{10^r}\right)\cdot {}^{11}C_{r+1} = \frac{\alpha^{11}-11^{11}}{10^{10}}

, then

\alpha

is equal to :

(1) $11$
(2) $15$
(3) $20$ Official answer
(4) $24$

Official answer

Option 3

NTA final key.

Chapter: Binomial Theorem
Topic: Binomial Coefficients
Idea tested: GP-Weighted Coefficient Sums

Same topic in other shifts

All Binomial Coefficients questions

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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.