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📐 Mathematics  ·  Probability  ·  JEE

A box has 5 good and 3 defective bulbs. P(2nd is defective given 1st was good) =

Answer: 3/7.

  • A 3/8
  • B 3/7
  • C 2/8
  • D 1/3

Correct answer: B. 3/7

Explanation: After removing 1 good bulb, 7 remain (5 good, 3 defective wait no: 4 good, 3 defective). P(defective) = 3/7.

UABA and BA onlyB onlyOutside both circles: complement of (A union B)

Venn diagram of the universal set U with events A and B, showing the intersection (A and B), the parts unique to each event, and the complement region outside both.

Concept context

Chance, events, conditional probability, and Bayes theorem

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