11-9

11-8

11-7

11-6

11-5

11-4

11-3

11-2

12-9

12-8

12-7

12-6

12-5

12-4

12-3

11

11

11

11

11

11

11

11

13-9

13-8

13-7

13-6

13-5

13-4

14-9

14-8

14-7

14-6

14-5

15-9

15-8

15-7

15-6

16-9

16-8

16-7

17-9

17-8

18-9

12

12

12

12

12

12

12

13

13

13

13

13

13

14

14

14

14

14

15

15

15

15

16

16

16

17

17

18

20以内退位减法表

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