subtraction [filling in the blanks]

• 16
• 18
• 17
• 12
• 13
• 21
• 14
• 15
• 10
• 19
• 11
• 20

11

-

1

=

12

-

1

=

13

-

1

=

14

-

1

=

15

-

1

=

16

-

1

=

17

-

1

=

18

-

1

=

19

-

1

=

20

-

1

=

21

-

1

=

22

-

1

=

Drag the numbers from the left hand list into the blank cells to complete each sum.