Complete the following number patterns.
- 551, 486, 421, , 291
- 42, 52, 63, 75, .
- 167, , 185, 190, 193
(a)
551 - 486 = 65
486 - 421 = 65
421 - 65 = 356
Pattern: Keep subtracting 65 from left to right.
(b)
52 - 42 = 10
63 - 52 = 11 (1 is added to 10)
75 - 63 = 12 (1 is added to 11)
12 + 1 = 13
75 + 13 = 88
Pattern: Keep adding 1 to the previous added number from left to right.
(c)
193 - 190 = 3
190 - 185 = 5
185 - 7 = 178
178 - 11 = 167
Pattern: Keep subtracting 2 from the previous subtracted number from right to left.
Answer(s): (a) 356; (b) 88; (c) 178
