The figure shows a pattern formed using some chopsticks.
- How many chopsticks are used to form 42 squares?
- How many squares can be formed using 214 chopsticks?
(a)
Pattern for the number of chopsticks
1 square: 1 x 3 + 1 = 4
2 squares: 2 x 3 + 1 = 7
3 squares: 3 x 3 + 1 = 10
Formula
Number of chopsticks = Number of squares x 3 + 1
Number of chopsticks for 42 squares
= 42 x 3 + 1
= 127
(b)
Number of squares x 3 + 1 = 214
Number of squares x 3 = 214 - 1
Number of squares = 213 ÷ 3
Number of squares = 71
Answer(s): (a) 127; (b) 71