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The probability of meeting a random person who has the same birthday as you is 1/365 , which is approximately 0.27%. What is the probability that the 25th person you meet is the first person who has the same birthday as you?

User Vrunoa
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2 Answers

2 votes

Answer: 1. A) 0.14

2. C) 46%

3. D) 86%

4. B) 0.513

5. A) 0.003

6. C) 0.069

7. C) 0.25%

8. D) 0.03

9. C) 71%

10. A) 10%

Step-by-step explanation: 100% :)

User Anton Eliasson
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5.1k points
5 votes

Answer:

The required probability (P) is :


P =((364)/(365))^(24)\cdot (1)/(365)

Explanation:

Probability of meeting random person who has same birthday as you =
(1)/(365)

Probability of meeting random person who do not has same birthday as you =


1-(1)/(365)=(364)/(365)

Now, to find the required probability that the 25th person you meet is the first person who has the same birthday as you = (Probability that the first 24 persons we meet did not have same birthday as you) × (Probability that the first 25 persons we meet has same birthday as you)

Therefore,


P =((364)/(365))^(24)\cdot (1)/(365)

User Amir Reza Riahi
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