The odds of three friends having the same birthday (not a specific birthday, just the same birthday) can be calculated by using the principles of probability.
Assuming that each year has 365 days (ignoring leap years), the probability for the first person is 1, because they can have their birthday on any day of the year.
Let’s call these friends A, B, and C.
– The probability of friend B having the same birthday as friend A is 1/365 because there is only one day on which B can have a birthday that matches A’s.
– The probability of friend C also having the same birthday as A (and therefore B) is again 1/365.
Multiplying these probabilities together, the probability of all three friends having the same birthday is 1 * 1/365 * 1/365 = 1/133,225.
So the odds of three friends having the same birthday are 1 in 133,225.