The figure shows a pattern formed using some matchsticks.
- How many matchsticks are used to form 73 squares?
- How many squares can be formed using 172 matchsticks?
(a)
Pattern for the number of matchsticks
1 square: 1 x 3 + 1 = 4
2 squares: 2 x 3 + 1 = 7
3 squares: 3 x 3 + 1 = 10
Formula
Number of matchsticks = Number of squares x 3 + 1
Number of matchsticks for 73 squares
= 73 x 3 + 1
= 220
(b)
Number of squares x 3 + 1 = 172
Number of squares x 3 = 172 - 1
Number of squares = 171 ÷ 3
Number of squares = 57
Answer(s): (a) 220; (b) 57
