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Unit 2 Practice

Many people looking at NOVA find decimals more familiar than fractions because they work with money every day. If this sounds right to you, use this foundational fact to convert fractions into decimals to help you play to your strengths.

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This interactive shows how to multiply decimals. (You can use it to add fractions up to 3.0, too!)

How to Multiply and Divide with Decimals

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Converting between fractions, decimals and percents

We have talked a lot about fractions, decimals and numbers. Those core ideas will help you see how they are related. You know that 1/2 = 0.5 = 50%. You can divide 1 / 2 to find that the answer is 0.5 and you know that if something is 50% off, then it costs 1/2 as much. These two videos are 3-minutes long and give you the quick deep dive on how to convert between any numbers.

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The big idea is that these type of numbers can represent similar numbers. The key to convert from fractions to other numbers is to divide the top number by the bottom number. Decimals and percents are very closely related. The only percents that may be surprising to you are fractions greater than 100%. If a bank account with $50 increases by 120%, then the increase is $50 x 1.2 = $60.

Word Problems

The new word problem idea is to make sure you use the correct units in your answer. In the actual question, underline the unit if you think you may forget it. Sometimes a word problem will give you all the measurements in inches and then ask for the answer in feet. You will need to remember to convert inches to feet. You may need to convert the answer after you calculate it (Example 1) or after you calculate it (Example 2). Here’s an example:

  • Example 1. A tile is 40 centimeters long and 10 centimeters tall. What is the area of the tile in square meters?
  • Example 2. Pauley has 24 toy cars end-to-end on a shelf. Each car is 3 inches long. How long must the shelf be?

What’s great about these types of word problems is that we are using real-life to understand fractions and decimals so the word problems may even be easier.

By the way, Example 1 is answer 0.4 meters x 0.1 meters = 0.04 square meters. For example 2, the cars cover 24×3 inches = 72 inches, which is 72/12 = 6 feet.

You can leave comments below if you have questions!