Mathematics · 2021
JEE Main · 4 August 2021, Shift 2 · Q78
A bag contains four bulbs. Some of these bulbs are defective. Two bulbs are drawn at random and it is found that both the bulbs are defective. What…
A bag contains four bulbs. Some of these bulbs are defective. Two bulbs are drawn at random and it is found that both the bulbs are defective. What is the probability that the bag contains exactly $\displaystyle 3$ defective bulbs?
Official answer
(2)
$\displaystyle 0.3$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.