math

adding

100

1+5

6

200

3+4

7

300

103+47

150

400

20+54

74

500

500+60

560

timing

100

2x2

4

200

1x1

1

300

4x1

4

400

3x5

15

500

2x5

10

Subtracting

100

20-2

18

200

15-2

13

300

68-8

60

400

23-3

20

500

43-3

40

timing 2 digit

100

10x1

10

200

10x3

30

300

10x20

200

400

10x8

80

500

10x6

60