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Extra Challenge
100

4+4

8

100

10-2

8

100

18+2

20
100

20-6

14

100
100+15
115
200

2+8

10

200

5-3

2

200

15+3

18

200

23-3

3

200

35-6

29

300

7+6

13

300

12-5

6
300

16+5

21

300

14-7=

7

300

78+3

81

400

8+7

15

400

18-9

9

400

22+24

46

400

17-5=

12
400

27-9

18

500

12+5

17

500

10-8

2
500

9+8

17

500

25-5=

20
500

55+8

63