For each of the seven months containing 31 days, the probability of being born in that month is 31/365. For each of the four months containing 30 days, the probability of being born in that month is 30/365. For February which contains 28 days, the probability of being born in that month is 28/365.
What is the probability that 12 persons will celebrate birthday in the same month?
Quite simply the answer is 1/12. Solution: A person can have birthday in any of the 12 months of the year. Another person can also have his/her birthday in any of the 12 months.
What is the probability that date of birth of a person is in the month of January?
of the binomial distribution is correct. We can use this and the binomial distribution to estimate the probability of seeing a range of results. I will use p(born Jan) = 31/365 ~ 0.085.
What’s the probability of two people being born in the same month?
1/12 probability
Let the first person’s birth month be x. Now, the second person must born in the same month (1/12 probability) to satisfy the given condition as both their births are independent events. So, required probability is 1/12 . So, 5 is the answer.
What is the probability of having a shared birth month in a group of 5 people?
All five people can be born in the same month in 12 ways (one for each month). You could have four in one month and one in another in 660 ways. You could have three in one month and two in another in 1,320 ways.
What is the probability of your friend being born in April?
(365/365) * (1/365) = 1/365, or about 0.27%.
Which birth month is the smartest?
September
Those born in September are, apparently, the smartest out of the entire year. According to Marie Claire, a study published in the National Bureau of Economic Research found that there’s a clear correlation between the month during which you were born and how smart you are.
What is the probability of being born any day of the year?
The probability of being born any day of the year is 1 or more specifically: 365/365. Since Person B must be born on the same day as Person A their probability is 1/365. We want both of these events to happen so multiply the probabilities: The probability that any randomly chosen 2 people share the same birthdate.
What’s the probability of being born on Dec 16?
A value of 1 (like Dec 16) means that a random person has the same probability of being born on that day as you would expect from a uniform distribution. A value lower than one (notably Jan 1, Jul 4, and Dec 24–26) means that a random person is that many times less likely to be born on that day than if the day were chosen uniformly at random.
What is the probability of the next student being born?
The next student is now limited to 364 possible days, so the second student’s probability is 364/365. The third student may be born on any of the remaining 363 days, so 363/365. This pattern continues so that our last student has a probability of 336/365 (365 – 29 days since the students before her used up 29 potential days).
What are the odds that nobody has a birthday on February 29th?
Assume that nobody has a birthday on February 29th and that their birthdays are random variables uniformly distributed across the other 365 days of the year. Find the minimum value of n such that the probability of at least two students sharing a birthday is at least 50%.
