Subtraction: Adding UP

Category 1

The whole is a multiple of ten.

20 – 1520 – 1420 – 1220 – 11

20 – 1020 – 920 – 720 – 8

30 – 2530 – 2330 – 1530 – 12

30 – 1930 – 1430 – 2430 – 21

40 – 3440 – 2940 – 2040 – 18

40 – 3240 – 2840 – 1940 – 24

50 – 3950 – 4450 – 2450 – 33

60 – 4960 – 2960 – 3960 – 19

70 – 5970 – 3470 – 4970 – 18

Category 2

The whole is a no longer multiple of ten but is below fifty.

15 – 915 – 915 – 915 – 9

21 – 1021 – 921 – 7 21 – 8

25 – 1925 – 1625 – 1825 – 9

23 – 1923 – 1623 – 1423 – 9

31 – 2931 – 2631 – 2431 – 15

32 – 2832 – 2532 – 1932 – 15

44 – 3944 – 3544 – 2944 – 25

41 – 3441 – 2841 – 2441 – 19

23 – 1933 – 1942 – 2941 – 18

Category 3

Mixture of numbers that lend themselves to the Adding Up Strategy

20 – 1424 – 1922 – 1326 – 17

30 – 1533 – 1933 – 1436 – 27

40 – 1945 – 1942 – 2342 – 34

50 – 2450 – 3956 – 2856 – 17

60 – 4960 – 2763 – 5663 – 19

70 – 6170 – 3474 – 4974 – 36

80 – 3980 – 6881 – 4981 – 58

90 – 7990 – 7492 – 8992 – 69

100 – 97100 – 89100 – 49100 – 24