Math 7 · Unit 3, Lesson 3
Signed Fractions and Decimals
Adding and subtracting fractions and decimals with signs
Rational numbers are all the numbers that can be written as a fraction, positive or negative. That includes fractions, decimals, and mixed numbers. The rules for adding and subtracting work the same for all of them.
Parts of a dollar follow the same rules as whole dollars. Don't ever subtract signed numbers. Change it to adding the opposite, then add.
Write it down. Do every change on paper, one line per step. Changing signs in your head is the number one reason for missed problems. If you changed something, it should be on the paper.
Go in order. Each tile has a short explanation, then a "Let me try a few" button.
When you have finished
At the end of each tile you will find a review form to give us feedback.
NC standard: NC.7.NS.1.