Question

Elijah wants to conduct a survey as to whether music CDs should be added to the items sold in the school store. Which sampling method will offer Elijah the best results?
Interview every student in the school band.


Interview every student attending the local outdoor concert.


Interview every student wearing earbuds in the cafeteria.


Interview every 5th student who enters the building in the morning.

Answer 1

Elijah should interview every 5th student who enters the building in the morning. It would be a stratified sampling where Elijah will take a sample from each one out of five students.

The other methods would be a biased sampling as students who are in a school band or attending a concert or wearing earbuds in the cafeteria would likely to give a 'yes' answer.