JEE Main 2025 — Probability Question with Solution
JEE Main 2025 (4 Apr Shift 1)
Question
A box contains 10 pens of which 3 are defective. A sample of 2 pens is drawn at random and let denote the number of defective pens. Then the variance of X is
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Show full solutionCorrect option: B
Correct answer
B
Step-by-step explanation
\begin{array}{|r|c|c|c|}\hline x & \mathrm{x}=0 & \mathrm{x}=1 & \mathrm{x}=2 \\\hline \mathrm{P}(\mathrm{x}) & \frac{{ }^7 \mathrm{C}_2}{{ }^{10} \mathrm{C}_2} & \frac{{ }^7 \mathrm{C}_1^3 \mathrm{C}_1}{{ }^{10} \mathrm{C}_2} & { }^3{ }^{10} \mathrm{C}_2 \\\hline\end{array}
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This is a previous-year question from JEE Main 2025, covering the Probability chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.