The figure shows a pattern formed using some matchsticks.
- How many matchsticks are used to form 87 squares?
- How many squares can be formed using 475 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 87 squares
= 87 x 3 + 1
= 262
(b)
Number of squares x 3 + 1 = 475
Number of squares x 3 = 475 - 1
Number of squares = 474 ÷ 3
Number of squares = 158
Answer(s): (a) 262; (b) 158