Question

Kelvin and Lewie each design surveys in order to determine the average number of people who buy food at the mall. Kelvin surveys every other person leaving the food area. Lewie surveys every fifth person leaving the mall’s main entrance. Which best explains which student’s survey is likely to produce less valid results?

Answer 1

I can't find the choices, but consider where each person is getting their sample from

- kelvin is sampling from people leaving the food area
- lewie is sampling from people leaving the main entrance

if they want to know the percentage of mall-goers who buy food, which person do you think is producing a less-biased sample?