Fact Families

Do you know what a fact family is? A fact family is a bunch of numbers that all work together… Here is an example: 6+4=10 10-6=4 4+6=10 10-4=6

In every fact family there are three numbers. For example: 10 7 3 When you have a fact family, you have to use the same numbers all the time…

Or you can subtract the numbers… You can add the numbers… 3+7=10 Or you can subtract the numbers… 10-7=3

When you add the numbers it doesn’t matter what order you add them. The solution always comes out the same 7+3=10 3+7=10

have to put the biggest number first… When you subtract you ALWAYS have to put the biggest number first… 10-7=3 10-3=7

1+2=3 2+1=3 3-1=2 3-2=1

3+2=5 2+3=5 5-2=3 5-3=2

What family number is missing? 1 3 ? 2 What family number is missing? How do you know? + + = 1 2 = 3 2 1 3 - - = 3 2 = 1 3 1 2

What family number is missing? 2 4 ? 2 What family number is missing? How do you know? + 2 2 = 4 - 2 4 2 =

What family number is missing? 1 4 ? 3 What family number is missing? How do you know? + - = 1 3 = 4 4 1 3 - + = 3 1 = 4 4 3 1

What family number is missing? 1 5 ? 4 What family number is missing? How do you know? + + = 1 4 = 5 4 1 5 - - = 5 1 = 4 5 4 1

What family number is missing? 2 5 ? 3 What family number is missing? How do you know? + + = 2 3 = 5 3 2 5 - - = 5 2 = 3 5 3 2

What family number is missing? 1 6 ? 5 What family number is missing? How do you know? + + = 1 5 = 6 5 1 6 - - = 6 1 = 5 6 5 1

What family number is missing? 2 6 ? 4 What family number is missing? How do you know? + + = 2 4 = 6 4 2 6 - - = 6 2 = 4 6 4 2

What family number is missing? 3 ? 6 3 What family number is missing? How do you know? + - = 3 3 = 6 6 3 3

What family number is missing? 1 7 ? 6 What family number is missing? How do you know? + + = 1 6 = 7 6 1 7 - - = 7 1 = 6 7 6 1

What family number is missing? 2 7 ? 5 What family number is missing? How do you know? + + = 2 5 = 7 5 2 7 - - = 7 2 = 5 7 5 2

What family number is missing? 3 7 ? 5 What family number is missing? How do you know? + + = 3 4 = 7 4 3 7 - - = 7 3 = 4 7 4 3

What family number is missing? 1 8 ? 7 What family number is missing? How do you know? + + = 1 7 = 8 7 1 8 - - = 8 1 = 7 8 7 1

What family number is missing? 2 8 ? 6 What family number is missing? How do you know? + + = 2 6 = 8 6 2 8 - - = 8 6 = 2 8 2 6

What family number is missing? 3 8 ? 5 What family number is missing? How do you know? + + = 3 5 = 8 5 3 8 - - = 8 3 = 5 8 5 3

What family number is missing? 4 ? 8 4 What family number is missing? How do you know? + - = 4 4 = 8 8 4 4

What family number is missing? 1 9 ? 8 What family number is missing? How do you know? + + = 1 8 = 9 8 1 9 - - = 9 1 = 8 9 8 1

What family number is missing? 2 9 ? 7 What family number is missing? How do you know? + + = 2 7 = 9 7 2 9 - - = 9 2 = 7 9 7 2

What family number is missing? 3 9 ? 6 What family number is missing? How do you know? + + = 3 6 = 9 6 3 9 - - = 9 3 = 6 9 6 3

What family number is missing? 4 9 ? 5 What family number is missing? How do you know? + + = 4 5 = 9 5 4 9 - - = 9 4 = 5 9 5 4

What family number is missing? 1 10 ? 9 What family number is missing? How do you know? + + = 1 9 = 10 9 1 10 - - = 10 1 = 9 10 9 1

What family number is missing? 2 10 ? 8 What family number is missing? How do you know? + + = 2 8 = 10 8 2 10 - - = 10 2 = 8 10 8 2

What family number is missing? 3 10 ? 7 What family number is missing? How do you know? + + = 3 7 = 10 7 3 10 - - = 10 3 = 7 10 7 3

What family number is missing? 4 10 ? 6 What family number is missing? How do you know? + + = 4 6 = 10 6 4 10 - - = 10 4 = 6 10 6 4

What family number is missing? 5 10 ? 5 What family number is missing? How do you know? + - = 5 5 = 10 10 5 5

What family number is missing? 1 11 ? 10 What family number is missing? How do you know? + + = 1 10 = 11 10 1 11 - - = 11 1 = 10 11 10 1

What family number is missing? 2 11 ? 9 What family number is missing? How do you know? + + = 2 9 = 11 9 2 11 - - = 11 2 = 9 11 9 2

What family number is missing? 3 11 ? 8 What family number is missing? How do you know? + + = 3 8 = 11 8 3 11 - - = 11 3 = 8 11 8 3

What family number is missing? 4 11 ? 7 What family number is missing? How do you know? + + = 4 7 = 11 7 4 11 - - = 11 4 = 7 11 7 4

What family number is missing? 5 11 ? 6 What family number is missing? How do you know? + + = 5 6 = 11 6 5 11 - - = 11 5 = 6 11 6 5

What family number is missing? 1 12 ? 11 What family number is missing? How do you know? + + = 1 11 = 12 11 1 12 - - = 12 1 = 11 12 11 1

What family number is missing? 2 12 ? 10 What family number is missing? How do you know? + + = 2 10 = 12 10 2 12 - - = 12 2 = 10 12 10 2

What family number is missing? 3 12 ? 9 What family number is missing? How do you know? + + = 3 9 = 12 9 3 12 - - = 12 3 = 9 12 9 3

What family number is missing? 4 12 ? 8 What family number is missing? How do you know? + + = 4 8 = 12 8 4 12 - - = 12 4 = 8 12 8 4

What family number is missing? 5 12 ? 7 What family number is missing? How do you know? + + = 5 7 = 12 7 5 12 - - = 12 5 = 7 12 7 5

What family number is missing? 6 12 ? 6 What family number is missing? How do you know? + - = 6 6 = 12 12 6 6

What family number is missing? 1 13 ? 12 What family number is missing? How do you know? + + = 1 12 = 13 12 1 13 - - = 13 1 = 12 13 12 1

What family number is missing? 2 13 ? 11 What family number is missing? How do you know? + + = 2 11 = 13 11 2 13 - - = 13 2 = 11 13 11 2

What family number is missing? 3 13 ? 10 What family number is missing? How do you know? + + = 3 10 = 13 10 3 13 - - = 13 3 = 10 13 10 3

What family number is missing? 4 13 ? 9 What family number is missing? How do you know? + + = 4 9 = 13 9 4 13 - - = 13 4 = 9 13 9 4

What family number is missing? 5 13 ? 8 What family number is missing? How do you know? + + = 5 8 = 13 8 5 13 - - = 13 5 = 8 13 8 5

What family number is missing? 6 13 ? 7 What family number is missing? How do you know? + + = 6 7 = 13 7 6 13 - - = 13 6 = 7 13 7 6

What family number is missing? 1 14 ? 13 What family number is missing? How do you know? + + = 1 13 = 14 13 1 14 - - = 14 1 = 13 14 13 1

What family number is missing? 2 14 ? 12 What family number is missing? How do you know? + + = 2 12 = 14 12 2 14 - - = 14 2 = 12 14 12 2

What family number is missing? 3 14 ? 11 What family number is missing? How do you know? + + = 3 11 = 14 11 3 14 - - = 14 3 = 11 14 11 3

What family number is missing? 4 14 ? 10 What family number is missing? How do you know? + + = 4 10 = 14 10 4 14 - - = 14 4 = 10 14 10 4

What family number is missing? 5 14 ? 9 What family number is missing? How do you know? + + = 5 9 = 14 9 5 14 - - = 14 5 = 9 14 9 5

What family number is missing? 6 14 ? 8 What family number is missing? How do you know? + + = 6 8 = 14 8 6 14 - - = 14 6 = 8 14 8 6

What family number is missing? 7 14 ? 7 What family number is missing? How do you know? + - = 7 7 = 14 14 7 7

What family number is missing? 1 15 ? 14 What family number is missing? How do you know? + + = 1 14 = 15 14 1 15 - - = 15 1 = 14 15 14 1

What family number is missing? 2 15 ? 13 What family number is missing? How do you know? + + = 2 13 = 15 13 2 15 - - = 15 2 = 13 15 13 2

What family number is missing? 3 15 ? 12 What family number is missing? How do you know? + + = 3 12 = 15 12 3 15 - - = 15 3 = 12 15 12 3

What family number is missing? 4 15 ? 11 What family number is missing? How do you know? + + = 4 11 = 15 11 4 15 - - = 15 4 = 11 15 11 4

What family number is missing? 5 15 ? 10 What family number is missing? How do you know? + + = 5 10 = 15 10 5 15 - - = 15 5 = 10 15 10 5

What family number is missing? 6 15 ? 9 What family number is missing? How do you know? + + = 6 9 = 15 9 6 15 - - = 15 6 = 9 15 9 6

What family number is missing? 7 15 ? 8 What family number is missing? How do you know? + + = 7 8 = 15 8 7 15 - - = 15 7 = 8 15 8 7

What family number is missing? 1 16 ? 15 What family number is missing? How do you know? + + = 1 15 = 16 15 1 16 - - = 16 1 = 15 16 15 1

What family number is missing? 2 16 ? 14 What family number is missing? How do you know? + + = 2 14 = 16 14 2 16 - - = 16 2 = 14 16 14 2

What family number is missing? 3 16 ? 13 What family number is missing? How do you know? + + = 3 13 = 16 13 3 16 - - = 16 3 = 13 16 13 3

What family number is missing? 4 16 ? 12 What family number is missing? How do you know? + + = 4 12 = 16 12 4 16 - - = 16 4 = 12 16 12 4

What family number is missing? 5 16 ? 11 What family number is missing? How do you know? + + = 5 11 = 16 11 5 16 - - = 16 5 = 11 16 11 5

What family number is missing? 6 16 ? 10 What family number is missing? How do you know? + + = 6 10 = 16 10 6 16 - - = 16 6 = 10 16 10 6

What family number is missing? 7 16 ? 9 What family number is missing? How do you know? + + = 7 9 = 16 9 7 16 - - = 16 7 = 9 16 9 7

What family number is missing? 8 16 ? 8 What family number is missing? How do you know? + + = 8 8 = 16 16 8 8

What family number is missing? 1 17 ? 16 What family number is missing? How do you know? + + = 1 16 = 17 16 1 17 - - = 17 1 = 16 17 16 1

What family number is missing? 2 17 ? 15 What family number is missing? How do you know? + + = 2 15 = 17 15 2 17 - - = 17 2 = 15 17 15 2

What family number is missing? 3 17 ? 14 What family number is missing? How do you know? + + = 3 14 = 17 14 3 17 - - = 17 3 = 14 17 14 3

What family number is missing? 4 17 ? 13 What family number is missing? How do you know? + + = 4 13 = 17 13 4 17 - - = 17 4 = 13 17 13 4

What family number is missing? 5 17 ? 12 What family number is missing? How do you know? + + = 5 12 = 17 12 5 17 - - = 17 5 = 12 17 12 5

What family number is missing? 6 17 ? 11 What family number is missing? How do you know? + + = 6 11 = 17 11 6 17 - - = 17 6 = 11 17 11 6

What family number is missing? 7 17 ? 10 What family number is missing? How do you know? + + = 7 10 = 17 10 7 17 - - = 17 7 = 10 17 10 7

What family number is missing? 8 17 ? 9 What family number is missing? How do you know? + + = 8 9 = 17 9 8 17 - - = 17 8 = 9 17 9 8

What family number is missing? 1 18 ? 17 What family number is missing? How do you know? + 18 + = 1 17 = 17 1 18 - = 17 - = 18 1 18 17 1

What family number is missing? 2 18 ? 16 What family number is missing? How do you know? + 18 + = 2 16 = 16 2 18 - = 16 - = 18 2 18 16 2

What family number is missing? 3 18 ? 15 What family number is missing? How do you know? + 18 + = 3 15 = 15 3 18 - = 15 - = 18 3 18 15 3

What family number is missing? 4 18 ? 14 What family number is missing? How do you know? + 18 + = 4 14 = 14 4 18 - = 14 - = 18 4 18 14 4

What family number is missing? 5 18 ? 13 What family number is missing? How do you know? + 18 + = 5 13 = 13 5 18 - = 15 - = 18 3 18 15 3

What family number is missing? 6 18 ? 12 What family number is missing? How do you know? + 18 + = 6 12 = 12 6 18 - = 16 - = 18 2 18 16 2

What family number is missing? 7 18 ? 11 What family number is missing? How do you know? + 18 + = 7 11 = 11 7 18 - = 11 - = 18 7 18 11 7

What family number is missing? 8 18 ? 10 What family number is missing? How do you know? + 18 + = 8 10 = 10 8 18 - = 10 - = 18 8 18 10 8

What family number is missing? 9 18 ? 9 What family number is missing? How do you know? + 18 - = 9 9 = 18 9 9

What family number is missing? 1 19 ? 18 What family number is missing? How do you know? + 19 + = 1 18 = 18 1 19 - = 18 - = 19 1 19 18 1

What family number is missing? 2 19 ? 17 What family number is missing? How do you know? + 19 + = 2 17 = 17 2 19 - = 17 - = 19 2 19 17 2

What family number is missing? 3 19 ? 16 What family number is missing? How do you know? + 19 + = 3 16 = 16 3 19 - = 16 - = 19 3 19 16 3

What family number is missing? 4 19 ? 15 What family number is missing? How do you know? + 19 + = 4 15 = 15 4 19 - = 15 - = 19 4 19 15 4

What family number is missing? 5 19 ? 14 What family number is missing? How do you know? + 19 + = 5 14 = 14 5 19 - = 14 - = 19 5 19 14 5

What family number is missing? 6 19 ? 13 What family number is missing? How do you know? + 19 + = 6 13 = 13 6 19 - = 13 - = 19 6 19 13 6

What family number is missing? 7 19 ? 12 What family number is missing? How do you know? + 19 + = 7 12 = 12 7 19 - = 12 - = 19 7 19 12 7

What family number is missing? 8 19 ? 11 What family number is missing? How do you know? + 19 + = 8 11 = 11 8 19 - = 11 - = 19 8 19 11 8

What family number is missing? 9 19 ? 10 What family number is missing? How do you know? + 19 + = 9 10 = 10 9 19 - = 10 - = 19 9 19 10 9

What family number is missing? 1 20 ? 19 What family number is missing? How do you know? + 20 + = 1 19 = 19 1 20 - = 19 - = 20 1 20 19 1

What family number is missing? 2 20 ? 18 What family number is missing? How do you know? + 20 + = 2 18 = 18 2 20 - = 18 - = 20 2 20 18 2

What family number is missing? 3 20 ? 17 What family number is missing? How do you know? + 20 + = 3 17 = 17 3 20 - = 17 - = 20 3 20 17 3

What family number is missing? 4 20 ? 16 What family number is missing? How do you know? + 20 + = 4 16 = 16 4 20 - = 16 - = 20 4 20 16 4

What family number is missing? 5 20 ? 15 What family number is missing? How do you know? + 20 + = 5 15 = 15 5 20 - = 15 - = 20 5 20 15 5

What family number is missing? 6 20 ? 14 What family number is missing? How do you know? + 20 + = 6 14 = 14 6 20 - = 14 - = 20 6 20 14 6

What family number is missing? 7 20 ? 13 What family number is missing? How do you know? + 20 + = 7 13 = 13 7 20 - = 13 - = 20 7 20 13 7

What family number is missing? 8 20 ? 12 What family number is missing? How do you know? + 20 + = 8 12 = 12 8 20 - = 12 - = 20 8 20 12 8

What family number is missing? 9 20 ? 11 What family number is missing? How do you know? + 20 + = 9 11 = 11 9 20 - = 11 - = 20 9 20 11 9

What family number is missing? 10 20 ? 10 What family number is missing? How do you know? + 20 - = 10 10 = 20 10 10

The End!