1. Comparative Relational Thinking
Addition

2. 765 = 756 5 = 3 + 2 FALSE TRUE Let’s Review
Are these equations true or false?
5 = 3 + 2
765 = 756
How do you know?
Talk me through your thinking…
FALSE
TRUE

3. How do you know the equation is true?
Let’s Review
Are these equations true or false?
4 + 6 = 3 + 7
4 + 2 = 5
How do you know the equation is true?
Talk me through your thinking…
FALSE
TRUE

4. How do you know the equation is true?
Let’s Review
Fill in the blank
4 + 6 = 8 + __
17 + __= 20
3 + 5 = n + 5
How do you know the equation is true?
How did you solve? 2
n = 3 3

5. What strategies do you use to add?
Let’s Review
What strategies do you use to add?
Count All
Make Doubles
Friendly Numbers
Make a Ten
Count On

6. Why do Friendly Numbers work?
17 + 8
Let’s think about an easy problem. 1 2 3 4 5 6 7 8
I will use the count up strategy first!
= 25

7. Why do Friendly Numbers work?
17 + 8
Let’s think about an easy problem.
Think = 5, Add 5 more
Add 3 to make 20 3 5
Now with friendly numbers…
Notice…
3 hops plus 5 hops is equal to 8!!!
= 25

8. Think about using Friendly Numbers to add…
-3 = 43
+3 = 30
Then I add 30 and 43 to find the sum.
= 73
If I add 3 to 27, then I need to take 3 from 46…46-3 = 43
I like to add with multiples of 10, so…
I need to add 3 to 27 to make 30.
The answer is 73!

9. Using Friendly Numbers in Comparative Relational Thinking
-4 = 13
+4 = 32
Let’s determine if this equation is TRUE or FALSE. = = =
If you add 4 to the 28, you need to take 4 from the 17.
You can use friendly numbers. Instead of making a 10, change one addend on one side to match the other side.
It does not matter which addend is matched…
BOTH addends MATCH, so it is TRUE!!!
17 – 4 is 13.
So, I can add 4 to 28 to get 32?
I don’t want to solve… I just want to COMPARE

10. Then I would subtract the value I added.
Using Friendly Numbers in Comparative Relational Thinking to find an Unknown
Find the unknown.
=  + 550
+ 7
- 7
550
760
The unknown is equal to 760!!
Then I would subtract the value I added.
First, I change the value of one addend to be the same as the addend on the other side of the equal sign.

11. True or False? =
false

12. True or False?
5, ,782 = 5, ,795
true

13. Find the missing addend.
= ___ + 300
= 300
346 – 13 = 333
Answer 333 Or
346 – 46 = 300
= = 333

14. Find the missing addend.