COMEDK · Maths · 36. Probability
A person writes four letters and address four envelopes. If the letters are placed in the envelopes at random, then the probability that not all letters are placed in the right envelope is
- A \(\dfrac{15}{24}\)
- B \(\dfrac{23}{24}\)
- C \(\dfrac{11}{24}\)
- D \(\dfrac{1}{24}\)
Answer & Solution
Correct Answer
(B) \(\dfrac{23}{24}\)
Step-by-step Solution
Detailed explanation
The total number of ways to place 4 letters into 4 envelopes is \(4! = 24\). The event that all letters are placed in the right envelope corresponds to exactly 1 way (each letter in its corresponding envelope). The probability that all letters are placed in the right envelope is…
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