Project ForgeDiscrete Mathematics
Probability & Combinatorics
GATE 2024
Medium
A bag contains 10 red balls and 15 blue balls. Two balls are drawn randomly without replacement. Given that the first ball drawn is red, the probability (rounded off to 3 decimal places) that both balls drawn are red is ____.
0.375(± 0.005 accepted)
Explanation
Given the first ball is red, 9 red balls remain out of 24 total remaining balls. P(second also red | first red) = 9/24 = 0.375.
Source: GATE CS 2024 (Session 1 / CS1) (2024)
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