The figure shows a pattern formed using some toothpicks.
- How many toothpicks are used to form 47 squares?
- How many squares can be formed using 145 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 47 squares
= 47 x 3 + 1
= 142
(b)
Number of squares x 3 + 1 = 145
Number of squares x 3 = 145 - 1
Number of squares = 144 ÷ 3
Number of squares = 48
Answer(s): (a) 142; (b) 48
