JEE Main Maths · Probability

Bayes' Theorem in JEE Main

Name: Bayes' Theorem: JEE Main previous year questions
Creator: Lumi

Bayes' Theorem (Maths, Probability) came 8 times in 8 of the 42 JEE Main shifts Lumi analysed, across 4 distinct ideas. 6 of them came in 2024–26; it was last asked in 2026.

Questions: 8; in 8 shifts
Ideas asked: 4; 2 asked more than once
Numerical answer: 1; 13% of its questions
Pattern: Asked most years; last asked 2026

Questions each year

In the shifts Lumi analysed for each year.

Difficulty and format

Easy 4Medium 4Hard 0

Format

Single correct7 Q
Numerical value1 Q

Ideas inside the topic

4 ideas

Bayes' Theorem Application4 Q
Theorem of Total Probability2 Q
Biased vs Unbiased Instrument Selection1 Q
Missing or Lost Card Scenarios1 Q

Where it sits

Part of Probability, which had 49 questions in all. Bayes' Theorem accounts for 16% of them. In Lumi's JEE taxonomy it belongs to Algebra.

Every question

All 8 Bayes' Theorem questions

Newest first, each with its options and official answer.

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
4 Apr 2025, Shift 2 · Q23A 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…MediumNumerical value
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
2 Sep 2020, Shift 1 · Q68Box I contains 30 cards numbered 1 to 30 and Box II contains 20 cards numbered 31 to 50. A box is selected at random and a card is drawn…MediumSingle correct