Question

Alejandro wants to determine the average shoe size of all of the male students in his school. Which sample is likely to yield the most biased results? A.every tenth boy on the school’s phone list B.every member of the boys’ basketball team C.every boy in a randomly selected ninth-, tenth-, eleventh-, and twelfth-grade gym class D.every fifth boy who walks through the front doors of the school in the morning

Answer 1

B. every member of the boys' basketball team

because people who play basketball are generally taller which means they have bigger feet (most of the time) which doesn't accurately represent the average of the male student body.

Answer 2

Option: B is the correct answer.

B. Every member of the boys’ basketball team

Explanation:

We know that a biased sample is one in which the sample is not random.

There is some partiality or some preference of choosing a member of a sample.

A.) Every tenth boy on the school’s phone list.

As the choosing of the members of a sample is random i.e. each student has an equal probability of getting chosen.

Hence, the sample is not biased.

C.) Every boy in a randomly selected ninth-, tenth-, eleventh-, and twelfth-grade gym class.

Again this sample is random.

Hence, the option is incorrect.

D.) Every fifth boy who walks through the front doors of the school in the morning.

In this sample every person has an equal probability.

Hence, the sample is not biased.

B.) Every member of the boys’ basketball team.

This is a biased sample since the members in the basketball team have a big height and hence their foot size is also big. So, we can't obtain a good result for determining the average shoe size of all the male students in the school.

Hence, the sample is biased.