Chapter 1

count on 

Start at 3  Count on 1 

number line 

 

Link: number line 

difference 

The answer to a subtraction problem. 

sum 

The answer to an addition problem. 

addend 

The addend is one of the numbers that is being added in order to find a sum. 

fact family 

3 + 6 = 9      6 + 3 = 9

9 - 6 = 3       9 - 3 = 6

 related facts

 The numbers of a fact family are related facts.

 turnaround facts

These are turnaround fact.  You can add 4+7 or 7+4 and still get the sum of 11. 

4+7=11

7+4=11