Probability with cake

Question

There are 20 classmates. a cake is cut into 10 slices. what is the probability of one of those classmates getting a slice of that cake?

Answer 1

The question needs to be a bit clearer, since there are two possible answers: 50% or 1/2 and 5% or 1/20.

Each classmate has a 50% chance of getting any of the slices of cake because the number of slices is half the number of classmates.

10 slices / 20 classmates = 1/2 = 50%

However, each classmate has a 5% chance of getting any particular slice of cake because there are now 20 classmates and one piece of cake they're all interested in.

1 slice / 20 classmates = 1/20 = 5%

The first solution is more realistic, unless there's something really special about one of the slices of cake.

Answer 2

1/20 each student

10 slices

1/20 * 10 = 12