Complete the following number patterns.
- 874, 824, 774, , 674
- 33, 42, 52, 63, .
- 62, , 79, 84, 87
(a)
874 - 824 = 50
824 - 774 = 50
774 - 50 = 724
Pattern: Keep subtracting 50 from left to right.
(b)
42 - 33 = 9
52 - 42 = 10 (1 is added to 9)
63 - 52 = 11 (1 is added to 10)
11 + 1 = 12
63 + 12 = 75
Pattern: Keep adding 1 to the previous added number from left to right.
(c)
87 - 84 = 3
84 - 79 = 5
79 - 7 = 72
72 - 10 = 62
Pattern: Keep subtracting 2 from the previous subtracted number from right to left.
Answer(s): (a) 724; (b) 75; (c) 72
