The figure shows a pattern formed using some toothpicks.
- How many toothpicks are used to form 70 squares?
- How many squares can be formed using 229 toothpicks?
(a)
Pattern for the number of toothpicks
1 square: 1 x 3 + 1 = 4
2 squares: 2 x 3 + 1 = 7
3 squares: 3 x 3 + 1 = 10
Formula
Number of toothpicks = Number of squares x 3 + 1
Number of toothpicks for 70 squares
= 70 x 3 + 1
= 211
(b)
Number of squares x 3 + 1 = 229
Number of squares x 3 = 229 - 1
Number of squares = 228 ÷ 3
Number of squares = 76
Answer(s): (a) 211; (b) 76