Q. EN: Determine the minimum number of students required in a class to ensure that at least three of them celebrate their birthdays in the same month.
Apply Pigeonhole Principle: Use the Pigeonhole Principle, which states that if n items are put into m containers, with n>m, then at least one container must contain more than one item.
Consider Months as Containers: There are 12 months in a year, so think of each month as a container for birthdays.
Ensure 13 Students for Birthdays: To ensure that at least two students have their birthdays in the same month, we would need 13 students (12 months + 1).
Need Three Students in Same Month: But we need at least 3 students to have their birthdays in the same month.
Scenario with 24 Students: If we have 2 students for each of the 12 months, that's 24 students, and all months could have exactly 2 birthdays.
Adding One More Student: Adding one more student 24+1 ensures that at least one month will have three birthdays.