Sarada and Hamida are friends. What is the probability that both will have (i) the same birthday? (ii) different birthdays? (ignoring a leap year).

Step 1: Analyse the given question and find the probability that both will have same birthday.
NOTE: Number of days in the year = 365
Sarada can take birth on any of the 365 days.
Now in order to have the same birthday hamida should take birth on the
same day. For example say if sarada birthday is 12 may then hamida
birthday should be 12 may.
So, the number of days when same birth is possible = 1
Then, the probability that both will have the same birthday = \frac{1}{365}
Step 2: Calculate the probability that both will have different birthdays.
If Hamida's birthday is different from Sarada's, the number of favourable
outcomes for her birthday = 365 - 1 = 364
Therefore, the probability that both will have different birthdays P (Hamida's birthday is different from Sarada's birthday) = \frac{364}{365}