Complete the following number patterns.
- 501, 403, 305, , 109
- 26, 32, 39, 47, .
- 78, , 91, 95, 97
(a)
501 - 403 = 98
403 - 305 = 98
305 - 98 = 207
Pattern: Keep subtracting 98 from left to right.
(b)
32 - 26 = 6
39 - 32 = 7 (1 is added to 6)
47 - 39 = 8 (1 is added to 7)
8 + 1 = 9
47 + 9 = 56
Pattern: Keep adding 1 to the previous added number from left to right.
(c)
97 - 95 = 2
95 - 91 = 4
91 - 6 = 85
85 - 7 = 78
Pattern: Keep subtracting 2 from the previous subtracted number from right to left.
Answer(s): (a) 207; (b) 56; (c) 85
