Complete the following number patterns.
- 672, 614, 556, , 440
- 42, 49, 57, 66, .
- 166, , 181, 186, 189
(a)
672 - 614 = 58
614 - 556 = 58
556 - 58 = 498
Pattern: Keep subtracting 58 from left to right.
(b)
49 - 42 = 7
57 - 49 = 8 (1 is added to 7)
66 - 57 = 9 (1 is added to 8)
9 + 1 = 10
66 + 10 = 76
Pattern: Keep adding 1 to the previous added number from left to right.
(c)
189 - 186 = 3
186 - 181 = 5
181 - 7 = 174
174 - 8 = 166
Pattern: Keep subtracting 2 from the previous subtracted number from right to left.
Answer(s): (a) 498; (b) 76; (c) 174
