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I'm trying to solve a birthday paradox problem, I'm really close to the answer but I guess I'm doing something wrong. The problem states that the probability of being born on a friday is $x$ and is equally probable to any other day of the week. Assuming 4 (or any number n people) where selected, what is the probability to have for example two born on friday and two born on other days of the week?

I know that the probability of two people sharing the same birthday is: $$\frac{(365*364*363*362)}{365^n}$$ Another note I was able to come to is that the chance of last two not sharing birthdays with the first two is: $$1-\frac{5}{7}*\frac{4}{7} \approx 0.591$$

Assuming that a person can be born on a Friday with probability 1/3 and with equal probability any other day of the week. What is the probability that among 4 randomly selected people, two were born on the same day and the other two in two other days?

The correct answer according to my exercise sheet is about $0.52$. Can anyone point me in the right direction?

I'm trying to solve a birthday paradox problem, I'm really close to the answer but I guess I'm doing something wrong. The problem states that the probability of being born on a friday is $\frac{1}{3}$ and is equally probable to any other day of the week. Assuming 4 (or any number n people) where selected, what is the probability to have for example two born on friday and two born on other days of the week?

I know that the probability of two people sharing the same birthday is: $$\frac{(365*364*363*362)}{365^n}$$ Another note I was able to come to is that the chance of last two not sharing birthdays with the first two is: $$1-\frac{5}{7}*\frac{4}{7} \approx 0.591$$

Assuming that a person can be born on a Friday with probability 1/3 and with equal probability any other day of the week. What is the probability that among 4 randomly selected people, two were born on the same day and the other two in two other days?

The correct answer according to my exercise sheet is about $0.52$. Can anyone point me in the right direction?

I'm trying to solve a birthday paradox problem, I'm really close to the answer but I guess I'm doing something wrong. The problem states that the probability of being born on a friday is x and is equally probable to any other day of the week. Assuming 4 (or any number n people) where selected, what is the probability to have for example two born on friday and two born on other days of the week?

I know that the probability of two people sharing the same birthday is: $$\frac{(365*364*363*362)}{365^n}$$ Another note I was able to come to is that the chance of last two not sharing birthdays with the first two is: $$1-\frac{5}{7}*\frac{4}{7} \approx 0.591$$

The correct answer according to my exercise sheet is about $0.52$. Can anyone point me in the right direction?

I'm trying to solve a birthday paradox problem, I'm really close to the answer but I guess I'm doing something wrong. The problem states that the probability of being born on a friday is $x$ and is equally probable to any other day of the week. Assuming 4 (or any number n people) where selected, what is the probability to have for example two born on friday and two born on other days of the week?

I know that the probability of two people sharing the same birthday is: $$\frac{(365*364*363*362)}{365^n}$$ Another note I was able to come to is that the chance of last two not sharing birthdays with the first two is: $$1-\frac{5}{7}*\frac{4}{7} \approx 0.591$$

Assuming that a person can be born on a Friday with probability 1/3 and with equal probability any other day of the week. What is the probability that among 4 randomly selected people, two were born on the same day and the other two in two other days?

The correct answer according to my exercise sheet is about $0.52$. Can anyone point me in the right direction?