Count on and Turn Around Facts
Which numbers are the addends?
4+8=12
4 and 8 are the addends
What is a double fact?
a double fact is an addition equation where a number is added to itself, such as 3 + 3 = 6.
What subtraction means?
What is the sign for subtraction?
Subtraction means your taking away something
-
10+7=
17
2+4+2 =
Jake draws 9 birds. Bobbi draws 2 birds. How many birds do they draw in all?
Which shows how to "count on" to solve the problem?
9 , 10 , 11
What is a near double fact?
Near doubles is a mental math strategy where you solve addition problems by relating them to known doubles facts, often by adding one more to a double.
Example 3+4=7
Count back 5 times starting with 10
10 in your head
9 , 8 , 7 , 6 , 5
What is the sum?
4+7= 10+1=
11
4+3+7 =
14
8+3=
_+_=
12
3+8=12
How could you use the doubles fact 7+7 to find 7+9?
7+9 is two more than 7+7
7+7,{ 7+8, 7+9}
Solve the equations
18-9= 8-5= 7-3=
9
3
4
15 (+) or (-) 3 = 18
(+) PLUS
Lisa saw 4 sheep, and 4 goats at the petting zoo. She also saw 3 pigs. How many animals did Lisa see at the petting zoo?
11 animals
Solve 15 - _= 6
What is the addition equation?
_+_=
15-9=6
9+6=15
Which double fact will help you find 8+9
8+8 double fact
Draw a number line and find
17-4=
13
16 (+) or (-) 6 = 10
(-) MINUS
How do you show which 2 numbers you are adding first?
You circle them.
When you flip the addends, the sum DOESN'T change is called what?
Turn Around Facts
or Turn Around Friends
Choose all that have a sum of 16
8+6 8+8 9+6 9+7 10+6
8+8
9+7
10+6
Make a Ten Frame Mat and Solve
16-9
7
Make a Ten Frame
15-_=5
What is the addition fact?
10
5+10=15
How do you decide which two numbers to add first?
Make 10, doubles facts or looks for facts you know.