Math 7 · Unit 3, Lesson 7: Rational Number Problems · Tile 4 of 4
Unit 3 Review
Every rule from the unit in one place
Every rule in Unit 3
This is every rule from Unit 3 on one card. Before you start a problem, find the operation, then use its rule. When you get one wrong, look back here and find which rule you skipped.
| Lesson | The rule |
|---|---|
| Lesson 1, Adding | Money you have is positive, money you owe is negative. Pay off what you can. What's left is the answer. |
| Lesson 2, Subtracting | Don't ever subtract signed numbers. Change it to adding the opposite. |
| Lesson 3, Fractions and decimals | Pick one form, then move numbers around to find friends. |
| Lesson 4, Multiplying | Same signs, positive. Different signs, negative. Count the negatives. |
| Lesson 5, Dividing | The same sign rules. The fraction bar means divide. Never divide by zero. Flip and multiply. |
| Lesson 6, Fractions to decimals | Divide the top by the bottom. The decimal stops or repeats. |
| Lesson 7, Putting it together | Groups first, then times and divide, then add. |
The rules for operating with integers extend to all rational numbers: fractions, decimals, and mixed numbers, positive and negative.
Every rule in this unit works for every kind of number. Whole numbers, fractions, decimals, it's all the same rules.
Elle and Finn talk it over
We finished Unit 3! Can we celebrate?
Yes. I'll bring negative three cupcakes.
So you owe me three cupcakes?
Fine. Times negative one. Now I'm bringing three.
Best math ever.
Unit 4 uses all of these rules with letters, called variables, mixed in.
NC standard: NC.7.NS.3.