If you have a prism with a volume of 15,625 units³ and have a second similar prism with a scale factor of 1:5, what will be the volume of the second prism?

When you are gathering information about a group (like in a survey), the whole group is called the population.

It is often not possible to survey every member of a population because the population could be so big, for this reason sometimes researchers study part of the group called the sample.

Let’s say Mrs. Allison wanted to know which subject middle school students in Tennessee liked the most in school. It would be impossible for her to survey every middle school student in the state. So, she might survey the middle school students at Lascassas. In this example, every middle school student in the state would be the population and the middle school students at Lascassas would be the sample.

In the following examples, identify the population and the sample.

A scientist studies lions on a wildlife preserve to learn the parenting habits of lions.

Mrs. Dorris surveys 100 students to see which type of books the students at Lascassas prefer.

Population Sample

Population Sample

A restaurant uses comment cards to find out about customer satisfaction.

This is tricky…not everyone fills out comment cards.

Population Sample

For a sample to be useful in a survey, it must be representative to the entire population.

A random sample is a sample that gives every person in the population a chance of being chosen.

In the restaurant comment card example, it would be random if comment cards were given to every customer that entered the restaurant.

It would not be a random sample if I only gave the women comment cards, because men would have no chance to be a part of the sample.

Determine if each situation is a random sample…did every member of the population have an opportunity?

The reporter questions only students that she knows personally.

This is not random because the students that the reporter did not know would not have a chance to speak to her.

The reporter questions every tenth student on an alphabetized list.

This is also not a random sample, because students who were not a multiple of 10 would have no chance of being chosen.

The reporter writes each name on a card and puts them in a bag and then questions the students whose name he draws from the hat.

This is a random sample, because students all have equal chance of being drawn out of the hat.

Identify the population and sample1. A scientist studies a pod of humpback

whales to find out about migration patterns of humpback whales in the wild.

The owner of a car lot is conducting a customer survey, tell whether each method is a random sample or not and explain.

2. The owner surveys customers on the lot one Sunday morning.

3. The owner randomly selects names from a list of all customers.

Population Sample