JEE Main 2023 — Probability Question with Solution
From: JEE Main 2023 (Online) 12th April Morning Shift
Question
A fair faces die is rolled repeatedly until a number less than appears. If the mean of the number of tosses required is , then is equal to ____________.
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Show full solutionCorrect answer: 10
Correct answer
10
Step-by-step explanation
In this case, the success is defined as getting a number less than when rolling an -sided die. The probability of success, , in each roll is then , and the probability of failure, , is .
......(1)
where
n = 10
......(1)
where
n = 10
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This is a previous-year question from JEE Main 2023, 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.