Show:
Subtraction - to 20
Addition + to 20
Subtraction - to 10
Addition + to 10
Addition and Subtraction to 20
100
12 - 8
What is 4
100
10+10
What is 20
100
5-5
What is 0
100
5+5`
What is 10
100
1+3
What is 4
200
14 - 5
What is 9
200
12+8
What is 20
200
5-2
What is 3
200
2+6
What is 8
200
10+1
What is 11
300
15-8
What is 7
300
13+5
What is 18
300
8-7
What is 1
300
7+3
What is 10
300
5-3
What is 2
400
20 - 13
What is 7
400
17+2
What is 19
400
9-5
What is 4
400
4+5
What is 9
400
10+2
What is 12
500
20-4
What is 16
500
16+3
What is 19
500
10-6
What is 4
500
4+3
What is 7
500
20-17
What is 3