Question

Consider the students in your statistics class as the population and suppose they are seated in four rows of 10 students each. To select a sample, you toss a coin. If it comes up heads, you use the 20 students sitting in the first two rows as your sample. If it comes up tails, you use the 20 students sitting in the last two rows as your sample. Does every student have an equal chance of being selected for the sample?

Answer 1

Given:
4 rows of ten students.

Probability of a head or tail in a coin toss is 1/2

head: 20 students sitting in the first two rows as your sample
1/2 * 1/20 = 1/40

tail: 20 students sitting in the last two rows as your sample.
1/2 * 1/20 = 1/40

Does every student have an equal chance of being selected for the sample?

Yes, every student have an equal chance of beings elected for the sample.