The figure shows a pattern formed using some wooden rods.
- How many wooden rods are used to form 19 squares?
- How many squares can be formed using 484 wooden rods?
(a)
Pattern for the number of wooden rods
1 square: 1 x 3 + 1 = 4
2 squares: 2 x 3 + 1 = 7
3 squares: 3 x 3 + 1 = 10
Formula
Number of wooden rods = Number of squares x 3 + 1
Number of wooden rods for 19 squares
= 19 x 3 + 1
= 58
(b)
Number of squares x 3 + 1 = 484
Number of squares x 3 = 484 - 1
Number of squares = 483 ÷ 3
Number of squares = 161
Answer(s): (a) 58; (b) 161
