Step 4

Difficulty 4

1. Add these 3 numbers: 14 + 5 + 2
2. Add these 3 numbers: 11 + 4 + 5
3. Add these 3 numbers: 13 + 7 + 6
4. Adding tens: 38 + 20 = ?
5. Adding tens: 56 + 30 = ?
6. Now Add This! 34+11, 34+12
7. Now Add This! 33+19, 33+21
8. Add three numbers: 14 + 7 + 3
9. Add three numbers: 10 + 12 + 8
10. Make 36: 20 + 14 + ?
11. Make 39: 30 + 6 + ?
12. Make 37: 12 + 20 + 5
13. Number detectives: 30+?, 50+?, 60+? =100
14. Add three numbers: 2 + 13 + 9
15. Add three numbers: 15 + 7 + 8
16. Add three numbers: 17 + 7 + 12
17. Number detectives: ? + 9 = 49
18. Number detectives: ? + 11 = 53
19. Crossing 100: 4 more than 99
20. Crossing 100: 7 more than 97
21. Crossing 100: 8 more than 98
22. Crossing 100: 9 more than 92
23. Crossing 100: 5 more than 97
24. True or False: 12+14=26
25. True or False: 12+12=24
26. True or False: 13+14=28
27. True or False: 15+12=27
28. True or False: 16+11=25
29. Same or Different: Click all the boxes with the answer 50.
30. Same or Different: Click all the boxes with the answer 46.
31. Same or Different: Click all the boxes with the answer 32.
32. Same or Different: Click all the boxes with the answer 45.
33. Same or Different: Click all the boxes with the answer 38.
34. Make 50: 39+7+? = 50
35. Make 50: 39+5+? = 50
36. Make 50: 35+5+? = 50
37. Make 50: 38+10+? = 50
38. Make 50: 42+6+? = 50
39. Beyond 70: 5 more than 79
40. Beyond 70: 9 more than 72
41. 36 + 12 = 48 So what else is true?
42. Add board 5* + 46 = *8
43. Add board 35 + *3 = 7*
44. Same or different:19-12,2+5,3+4,33-26,16-8
45. Use the pattern: 10, 20 & 80 - 5 = ?
46. Use the pattern: 10, 20 & 40 - 3 = ?
47. Use the pattern: 10, 20 & 90 - 7 = ?
48. Use the pattern: 10, 20 & 50 - 4 = ?
49. Use the pattern: 10, 20 & 30 - 8 = ?
50. Mysteries of Fifty: 50-?=48, 50-?=43
51. Mysteries of Fifty: 50-?=44, 50-?=47
52. Use the pattern 13-6=? 23-6=?, 33-6=?
53. Use the pattern 12-9=? 22-9=?, 32-9=?
54. Use the pattern 19-4=? 29-4=?, 39-4=?
55. The 9 family: Take 9, 19 & 29 from 57
56. Spot the difference between 20 and 39.
57. Spot the difference between 18 and 25.
58. Spot the difference between 25 and 34.
59. Spot the difference between 19 and 31.
60. Spot the difference between 19 and 42.
61. Spot the difference between 36 and 15.
62. Write the missing number: 20 + 3 + ? = 30
63. Write the missing number: 12 + ? + 10 = 30
64. Write the missing number: 15 + ? + 5 = 30
65. Write the missing number: 9 + ? + 12 = 30
66. Write the missing number: ? + 5 + 4 = 30
67. Write the missing number: 15 + ? + 6 = 30
68. Write the missing number: 20 + 3 + ? = 30
69. Number detectives: 30 - ? = 15
70. Number detectives: 30 - ? = 13
71. Taking Tens: 98 - 50
72. Taking Tens: 32 - 20
73. Taking Tens: 59 - 40
74. Taking Tens: 87 - 20
75. Taking Tens: 72 - 40
76. Subtract.chains 48 - 7 - 2 - 9, 35 - 4 - 3 - 8
77. Spot the difference: 50 & 41, 100 & 92, 101 & 98
78. Subtraction chains 80-6-5-3, 70-4-2-5
79. Subtraction chains 30-9-2-5, 60-5-4-3
80. Subtraction chains 40-5-6-3, 50-9-2-8
81. Subtraction chains 90-3-5-3, 40-2-8-5
82. Subtraction chains 60-9-2-3, 50-3-6-10
83. 19 go to Waterworld: 5+4+3+?
84. Make 50: 32+8+? = 50
85. Andrew at the shop: 50c - 25c
86. Madeline at the shop: 50c - 5c
87. Gavin at the shop: 60c + 10c
88. Damien at the shop: 10c + 5c
89. Jenny at the shop: 60c + 30c
90. Sarah at the shop: 50c + 40c