A girl’s name is ""Olivia Summer"" so her initials are OS. How many people need to be in an auditorium to ensure that at least 4 people in that room have the same pair of initials?

2704

Step-by-step explanation:

My probability math is a bit rusty, but here's my reasoning.

Assuming that it is a 1/26 chance someone has the same first inital as you (which isn't true, some initials are more prominent than others) and a 1/26 chance that somone has the same last inital as you (also not true) then it would be a 1/26 x 1/26 chance to find someone with the same first and last inital as you

To find 4 people in a room with the same inital would be 26 x 26 x 4, or 2704. If we are counting Olivia as a fifth person, then it would be 26 x 26 x 5, or 3380.

94

step-by-step explanation:

average the numbers and use a variable to figure out the minimum to get a 90.

(79+94+91+92+x)/5=90

x = 94