Fact Families

1
Fact Families
2
Do you know what a fact family is?

• A fact family is a bunch of numbers that all work
  together

Here is an example
6410 10-64
4610 10-46
3
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
4

• You can add the numbers

3710
Or you can subtract the numbers
10-73
5
When you add the numbers it doesnt matter what
order you add them.

• The solution always comes out the same

7310 3710
6
When you subtract you
ALWAYS
have to put the biggest number first

• 10-73 10-37

7
123
213
3-12
3-21
8

• 325

235
5-23
5-32
9
1
?
3
2

• What family number is missing?

How do you know?



1
2

3
2
1
3
-
-

3
2

1
3
1
2
10
2
?
4
2

• What family number is missing?

How do you know?

2
2

4
-
2
4
2

11
1
?
4
3

• What family number is missing?

How do you know?

-

1
3

4
4
1
3
-


3
1

4
4
3
1
12
1
?
5
4

• What family number is missing?

How do you know?



1
4

5
4
1
5
-
-

5
1

4
5
4
1
13
2
?
5
3

• What family number is missing?

How do you know?



2
3

5
3
2
5
-
-

5
2

3
5
3
2
14
1
?
6
5

• What family number is missing?

How do you know?



1
5

6
5
1
6
-
-

6
1

5
6
5
1
15
2
?
6
4

• What family number is missing?

How do you know?



2
4

6
4
2
6
-
-

6
2

4
6
4
2
16
3
?
6
3

• What family number is missing?

How do you know?

-

3
3

6
6
3
3
17
1
?
7
6

• What family number is missing?

How do you know?



1
6

7
6
1
7
-
-

7
1

6
7
6
1
18
2
?
7
5

• What family number is missing?

How do you know?



2
5

7
5
2
7
-
-

7
2

5
7
5
2
19
3
?
7
5

• What family number is missing?

How do you know?



3
4

7
4
3
7
-
-

7
3

4
7
4
3
20
1
?
8
7

• What family number is missing?

How do you know?



1
7

8
7
1
8
-
-

8
1

7
8
7
1
21
2
?
8
6

• What family number is missing?

How do you know?



2
6

8
6
2
8
-
-

8
6

2
8
2
6
22
3
?
8
5

• What family number is missing?

How do you know?



3
5

8
5
3
8
-
-

8
3

5
8
5
3
23
4
?
8
4

• What family number is missing?

How do you know?

-

4
4

8
8
4
4
24
1
?
9
8

• What family number is missing?

How do you know?



1
8

9
8
1
9
-
-

9
1

8
9
8
1
25
2
?
9
7

• What family number is missing?

How do you know?



2
7

9
7
2
9
-
-

9
2

7
9
7
2
26
3
?
9
6

• What family number is missing?

How do you know?



3
6

9
6
3
9
-
-

9
3

6
9
6
3
27
4
?
9
5

• What family number is missing?

How do you know?



4
5

9
5
4
9
-
-

9
4

5
9
5
4
28
1
?
10
9

• What family number is missing?

How do you know?



1
9

10
9
1
10
-
-

10
1

9
10
9
1
29
2
?
10
8

• What family number is missing?

How do you know?



2
8

10
8
2
10
-
-

10
2

8
10
8
2
30
3
?
10
7

• What family number is missing?

How do you know?



3
7

10
7
3
10
-
-

10
3

7
10
7
3
31
4
?
10
6

• What family number is missing?

How do you know?



4
6

10
6
4
10
-
-

10
4

6
10
6
4
32
5
?
10
5

• What family number is missing?

How do you know?

-

5
5

10
10
5
5
33
1
?
11
10

• What family number is missing?

How do you know?



1
10

11
10
1
11
-
-

11
1

10
11
10
1
34
2
?
11
9

• What family number is missing?

How do you know?



2
9

11
9
2
11
-
-

11
2

9
11
9
2
35
3
?
11
8

• What family number is missing?

How do you know?



3
8

11
8
3
11
-
-

11
3

8
11
8
3
36
4
?
11
7

• What family number is missing?

How do you know?



4
7

11
7
4
11
-
-

11
4

7
11
7
4
37
5
?
11
6

• What family number is missing?

How do you know?



5
6

11
6
5
11
-
-

11
5

6
11
6
5
38
1
?
12
11

• What family number is missing?

How do you know?



1
11

12
11
1
12
-
-

12
1

11
12
11
1
39
2
?
12
10

• What family number is missing?

How do you know?



2
10

12
10
2
12
-
-

12
2

10
12
10
2
40
3
?
12
9

• What family number is missing?

How do you know?



3
9

12
9
3
12
-
-

12
3

9
12
9
3
41
4
?
12
8

• What family number is missing?

How do you know?



4
8

12
8
4
12
-
-

12
4

8
12
8
4
42
5
?
12
7

• What family number is missing?

How do you know?



5
7

12
7
5
12
-
-

12
5

7
12
7
5
43
6
?
12
6

• What family number is missing?

How do you know?

-

6
6

12
12
6
6
44
1
?
13
12

• What family number is missing?

How do you know?



1
12

13
12
1
13
-
-

13
1

12
13
12
1
45
2
?
13
11

• What family number is missing?

How do you know?



2
11

13
11
2
13
-
-

13
2

11
13
11
2
46
3
?
13
10

• What family number is missing?

How do you know?



3
10

13
10
3
13
-
-

13
3

10
13
10
3
47
4
?
13
9

• What family number is missing?

How do you know?



4
9

13
9
4
13
-
-

13
4

9
13
9
4
48
5
?
13
8

• What family number is missing?

How do you know?



5
8

13
8
5
13
-
-

13
5

8
13
8
5
49
6
?
13
7

• What family number is missing?

How do you know?



6
7

13
7
6
13
-
-

13
6

7
13
7
6
50
1
?
14
13

• What family number is missing?

How do you know?



1
13

14
13
1
14
-
-

14
1

13
14
13
1
51
2
?
14
12

• What family number is missing?

How do you know?



2
12

14
12
2
14
-
-

14
2

12
14
12
2
52
3
?
14
11

• What family number is missing?

How do you know?



3
11

14
11
3
14
-
-

14
3

11
14
11
3
53
4
?
14
10

• What family number is missing?

How do you know?



4
10

14
10
4
14
-
-

14
4

10
14
10
4
54
5
?
14
9

• What family number is missing?

How do you know?



5
9

14
9
5
14
-
-

14
5

9
14
9
5
55
6
?
14
8

• What family number is missing?

How do you know?



6
8

14
8
6
14
-
-

14
6

8
14
8
6
56
7
?
14
7

• What family number is missing?

How do you know?

-

7
7

14
14
7
7
57
1
?
15
14

• What family number is missing?

How do you know?



1
14

15
14
1
15
-
-

15
1

14
15
14
1
58
2
?
15
13

• What family number is missing?

How do you know?



2
13

15
13
2
15
-
-

15
2

13
15
13
2
59
3
?
15
12

• What family number is missing?

How do you know?



3
12

15
12
3
15
-
-

15
3

12
15
12
3
60
4
?
15
11

• What family number is missing?

How do you know?



4
11

15
11
4
15
-
-

15
4

11
15
11
4
61
5
?
15
10

• What family number is missing?

How do you know?



5
10

15
10
5
15
-
-

15
5

10
15
10
5
62
6
?
15
9

• What family number is missing?

How do you know?



6
9

15
9
6
15
-
-

15
6

9
15
9
6
63
7
?
15
8

• What family number is missing?

How do you know?



7
8

15
8
7
15
-
-

15
7

8
15
8
7
64
1
?
16
15

• What family number is missing?

How do you know?



1
15

16
15
1
16
-
-

16
1

15
16
15
1
65
2
?
16
14

• What family number is missing?

How do you know?



2
14

16
14
2
16
-
-

16
2

14
16
14
2
66
3
?
16
13

• What family number is missing?

How do you know?



3
13

16
13
3
16
-
-

16
3

13
16
13
3
67
4
?
16
12

• What family number is missing?

How do you know?



4
12

16
12
4
16
-
-

16
4

12
16
12
4
68
5
?
16
11

• What family number is missing?

How do you know?



5
11

16
11
5
16
-
-

16
5

11
16
11
5
69
6
?
16
10

• What family number is missing?

How do you know?



6
10

16
10
6
16
-
-

16
6

10
16
10
6
70
7
?
16
9

• What family number is missing?

How do you know?



7
9

16
9
7
16
-
-

16
7

9
16
9
7
71
8
?
16
8

• What family number is missing?

How do you know?



8
8

16
16
8
8
72
1
?
17
16

• What family number is missing?

How do you know?



1
16

17
16
1
17
-
-

17
1

16
17
16
1
73
2
?
17
15

• What family number is missing?

How do you know?



2
15

17
15
2
17
-
-

17
2

15
17
15
2
74
3
?
17
14

• What family number is missing?

How do you know?



3
14

17
14
3
17
-
-

17
3

14
17
14
3
75
4
?
17
13

• What family number is missing?

How do you know?



4
13

17
13
4
17
-
-

17
4

13
17
13
4
76
5
?
17
12

• What family number is missing?

How do you know?



5
12

17
12
5
17
-
-

17
5

12
17
12
5
77
6
?
17
11

• What family number is missing?

How do you know?



6
11

17
11
6
17
-
-

17
6

11
17
11
6
78
7
?
17
10

• What family number is missing?

How do you know?



7
10

17
10
7
17
-
-

17
7

10
17
10
7
79
8
?
17
9

• What family number is missing?

How do you know?



8
9

17
9
8
17
-
-

17
8

9
17
9
8
80
1
?
18
17

• What family number is missing?

How do you know?

18


1
17

17
1
18
-

17
-

18
1
18
17
1
81
2
?
18
16

• What family number is missing?

How do you know?

18


2
16

16
2
18
-

16
-

18
2
18
16
2
82
3
?
18
15

• What family number is missing?

How do you know?

18


3
15

15
3
18
-

15
-

18
3
18
15
3
83
4
?
18
14

• What family number is missing?

How do you know?

18


4
14

14
4
18
-

14
-

18
4
18
14
4
84
5
?
18
13

• What family number is missing?

How do you know?

18


5
13

13
5
18
-

15
-

18
3
18
15
3
85
6
?
18
12

• What family number is missing?

How do you know?

18


6
12

12
6
18
-

16
-

18
2
18
16
2
86
7
?
18
11

• What family number is missing?

How do you know?

18


7
11

11
7
18
-

11
-

18
7
18
11
7
87
8
?
18
10

• What family number is missing?

How do you know?

18


8
10

10
8
18
-

10
-

18
8
18
10
8
88
9
?
18
9

• What family number is missing?

How do you know?

18
-

9
9

18
9
9
89
1
?
19
18

• What family number is missing?

How do you know?

19


1
18

18
1
19
-

18
-

19
1
19
18
1
90
2
?
19
17

• What family number is missing?

How do you know?

19


2
17

17
2
19
-

17
-

19
2
19
17
2
91
3
?
19
16

• What family number is missing?

How do you know?

19


3
16

16
3
19
-

16
-

19
3
19
16
3
92
4
?
19
15

• What family number is missing?

How do you know?

19


4
15

15
4
19
-

15
-

19
4
19
15
4
93
5
?
19
14

• What family number is missing?

How do you know?

19


5
14

14
5
19
-

14
-

19
5
19
14
5
94
6
?
19
13

• What family number is missing?

How do you know?

19


6
13

13
6
19
-

13
-

19
6
19
13
6
95
7
?
19
12

• What family number is missing?

How do you know?

19


7
12

12
7
19
-

12
-

19
7
19
12
7
96
8
?
19
11

• What family number is missing?

How do you know?

19


8
11

11
8
19
-

11
-

19
8
19
11
8
97
9
?
19
10

• What family number is missing?

How do you know?

19


9
10

10
9
19
-

10
-

19
9
19
10
9
98
1
?
20
19

• What family number is missing?

How do you know?

20


1
19

19
1
20
-

19
-

20
1
20
19
1
99
2
?
20
18

• What family number is missing?

How do you know?

20


2
18

18
2
20
-

18
-

20
2
20
18
2
100
3
?
20
17

• What family number is missing?

How do you know?

20


3
17

17
3
20
-

17
-

20
3
20
17
3
101
4
?
20
16

• What family number is missing?

How do you know?

20


4
16

16
4
20
-

16
-

20
4
20
16
4
102
5
?
20
15

• What family number is missing?

How do you know?

20


5
15

15
5
20
-

15
-

20
5
20
15
5
103
6
?
20
14

• What family number is missing?

How do you know?

20


6
14

14
6
20
-

14
-

20
6
20
14
6
104
7
?
20
13

• What family number is missing?

How do you know?

20


7
13

13
7
20
-

13
-

20
7
20
13
7
105
8
?
20
12

• What family number is missing?

How do you know?

20


8
12

12
8
20
-

12
-

20
8
20
12
8
106
9
?
20
11

• What family number is missing?

How do you know?

20


9
11

11
9
20
-

11
-

20
9
20
11
9
107
10
?
20
10

• What family number is missing?

How do you know?

20
-

10
10

20
10
10
108
The End!