**Chapter 3- Apply Subtraction Concepts**

Summary

**3-1 Count Back to Subtract:** I can count back to find the difference.

**Vocabulary:** Count back: on a number line with numbers, count from a higher number to a lower number. Subtract: to take away. Difference: the answer to a subtraction problem.

**3-2 Subtract All and Subtract Zero:** I can subtract all or none to find the difference.

**3-3 Use Doubles to Subtract:** I can use doubles facts to find the difference.

**3-4 PSS: Guess and Check:** I can use guess and check to solve problems.

**3-5 Relate Addition to Subtraction:** I can subtract from numbers through 20 using addition. I can identify and write different ways to name the same number.

**Vocabulary:** Related facts: a collection of 3 numbers that make up addition and subtraction facts. Inverse: operations that undo each other.

**3-6 Missing Addend:** I can find the missing number in addition and subtraction sentences.

**Vocabulary:** Missing Addend: a number that is absent from an addition sentence.

**3-7 Fact Families:** I can identify and write fact families.

**Vocabulary:** Fact Family: a group of related facts.

**3-8 PSS: Choose a Strategy:** I can choose the best strategy to solve problems.