Question

CAN SOMEONE PLZ HELP!!

Answer 1

The probability of at least 2 people in a group of n people sharing a common birthday can be expressed more easily (mathematically) as 1 minus the probability that nobody in the group shares a birthday.
Consider two people. The probability that they don't have a common birthday is 365/365 x 364/365. So the probability that they do share a birthday is 1-(365/365 x 364/365) = 1-365x364/365^2

Answer 2

Now consider 3 people. The probability that at least 2 share a common birthday is 1-365x364x363/365^3
And so on so that the probability that at least 2 people in a group of n people having the same birthday
= 1-(365x363x363x...x365-n+1)/365^n
= 1-365!/[ (365-n)! x 365^n ]

Answer 3

ok 1 step at a time. What do i do to solve a)?

Answer 4

I Have Given You A Basic Formula now jus put Values

Answer 5

Jus Replace n From 13

Answer 6

1-365!/[ (365-n)! x 365^n ]

Answer 7

i'm trying that but it's not coming out right.