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Suma
resta
suma dificil
100

8 + 2 =

What is 10?

100

10-5 = 

What is 5?

100

10 + ___ = 15

5

200

9 + 4 =

What is 13?

200

13 - 4 = 

What is 9?

200

9 + ___ = 13

4

300

7 + 8=

What is 15?

300

14 - 6 = 

What is 8?

300

___ + 7 = 17

10

400

10 + 7 + 2 =

What is 19?

400

16 - 7 = 

What is 9?

400

___ + 8 = 14

6

500

9 + 8 + 3 =

What is 20?

500

16 - 9 = 

What is 7?

500

__ + 7 = 15

8