JEE Main 2025 · MathsNumerical answerNumerical valueMediumMulti-step

JEE Main 4 April 2025, Shift 2, Maths Q23

Question 23 of 75 in this shift, Maths question 23 of 25, Section B.

A card from a pack of 52 cards is lost. From the remaining 51 cards, n cards are drawn and are found to be spades. If the probability of the lost card to be a spade is

\frac{11}{50}

, then n is equal to __________.

Official answer

NTA final key.

Chapter: Probability
Topic: Bayes' Theorem
Idea tested: Missing or Lost Card Scenarios

Same topic in other shifts

All Bayes' Theorem questions

6 Apr 2026, Shift 1 · Q10A bag contains $(\mathrm{N}+1)$ coins $-$ N fair coins, and one coin with 'Head' on both sides. A coin is selected at random and tossed.…EasySingle correct
8 Apr 2026, Shift 2 · Q6A candidate has to go to the examination centre to appear in an examination. The candidate uses only one means of transportation for the…EasySingle correct
2 Apr 2025, Shift 2 · Q9Given three indentical bags each containing 10 balls, whose colours are as follows : Bag I: Red 3, Blue 2, Green 5 Bag II: Red 4, Blue 3,…EasySingle correctHas a figure
7 Apr 2025, Shift 2 · Q10A bag contains 19 unbiased coins and one coin with head on both sides. One coin drawn at random is tossed and head turns up. If the…MediumSingle correct
30 Jan 2024, Shift 2 · Q20Bag A contains 3 white, 7 red balls and Bag B contains 3 white, 2 red balls. One bag is selected at random and a ball is drawn from it.…EasySingle correct
24 Jun 2022, Shift 1 · Q4Bag A contains 2 white, 1 black and 3 red balls and bag B contains 3 black, 2 red and n white balls. One bag is chosen at random and 2…MediumSingle 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.