All Questions
Tagged with birthday recreational-mathematics
5
questions
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What is the probability that three living people in the same family will celebrate their birthdays on exactly the same day.
I celebrate my birthday on the same day as one of my grandchildren. Just wonder how rare it would be for three people in the same family to celebrate their birthdays on the same day.
- 29
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Unclear how to prove this logarithmic reduction of a sequence, in reference to the birthday problem
On page 46 of Rouse Ball and HSM Coxeter's Mathematical Recreations and Essays, 13th ed., appears this step, in reference to the birthday problem
$$
(1-\frac{1}{365})(1-\frac{2}{365})...(1-\frac{n-1}{...
- 399
0
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What is the expected number of days of the year that are a birthday of at least one of n people?
I am new to probability and am just learning about the birthday problem. There is a sample problem that asks among a group of $n$ unrelated people, what is the expected number of days of the year that ...
- 41
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3
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If people sharing the same birthday raise their hand, how many hands do you expect to see raised?
The following question is taken from an interview book assuming that no calculator is provided.
Question: There are $25$ people at a party. One person asks everybody to annouycne their birthday, ...
- 15.9k
35
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Guessing the length of a playlist on "shuffle random?"
The other night I was hanging out with some friends and someone put on a playlist on shuffle random, where the songs are drawn uniformly at random from a fixed playlist. The person who put the ...
- 10.5k