1st Grade - 3 addends, fact families, missing addends

What are the 4 related facst in the fact family for 8 / 9 / 17

• 17-9=8

• 17+9=26

• 8+9=17

• 9+8=17

• 17-8=9

Which fact is missing?

7+8=15

15-8=7

15-7=8

• 8-7=1

• 15+8=23

• 15+7=22

• 8+7=15

2 + 8 + 7

• 12

• 18

• 17

• 19

6 + 9 + 4 =

• 17

• 18

• 19

• 20

6 + 4 + 3 =

• 10

• 11

• 12

• 13

6 + __ = 15

• 9

• 10

• 11

• 12

13 + __ = 17

• 2

• 3

• 4

• 5

8 + 9 + 1 =

• 16

• 17

• 18

• 19

3 + __ = 17

• 14

• 15

• 16

• 17

Which does not belong in the fact family?

• 5 + 9 = 14

• 5 + 14 = 9

• 9 + 5 = 14

• 14 - 9 = 5

• 14 - 5 = 9