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If you want to figure out something’s density, you divide how much the object weighs, its mass, by how big the object is, its volume. Write it like this: D = M/V.

However, before you can calculate density, you may need to determine several other measurements. For instance, you may need to determine the item’s volume first. Volume is the amount of 3-dimensional space that an object takes up. You will typically find units of volume measured in cubic inches, cubic feet, or cubic centimeters. You can calculate volume by multiplying the item’s area by its height.

Need to figure out the area? Area is the measure of the amount of flat surface that an object covers. It can be expressed in square inches, square feet, square miles, square centimeters, etc.

Understanding the definition of a perimeter may help, too. Perimeter describes the distance around an object. It is measured in units of length like inches, feet, miles, centimeters, or meters.

Volume, perimeter and area are measurements that are found all around us. As a class, think about the following problems and decide which of the following -- perimeter, area, or volume - is used to solve each problem.

1. The kitchen in your school's cafeteria is 15 feet long by 13 feet wide. How much surface do the cooks have to work in?

2. The inside of the ice-cream freezer at the local ice-cream parlor is 24 inches wide, 36 inches long and 24 inches deep. How much room is there for the ice cream?

3. If you walked around the school gymnasium, how many feet would the trip be?

4. The circumference of the average scoop of ice cream is 5 inches.

5. Suppose you are making salad dressing with 2/3 cup of oil and 1/3 cup of vinegar. Your jar will hold one cup. Is it big enough to hold all of the liquid?

Answers: 1. Area 2. Volume 3. Perimeter 4. Perimeter 5. Volume