Each of the figures is made up of 1-cm toothpicks.
The table shows the number of toothpicks used to make the figures and their perimeters.

1. Find the number of toothpicks in Figure 17.
2. What is the perimeter of Figure 59?
3. Which figure requires a total number of 3671 toothpicks?

(a)
Pattern for the number of toothpicks
Figure 1: 1 x 8 + 7 = 15
Figure 2: 2 x 8 + 7 = 23
Figure 3: 3 x 8 + 7 = 31

Formula:
Number of toothpicks = Pattern number x 8 + 7

Number of toothpicks in Figure 17
= 17 x 8 + 7
= 143

(b)
Pattern for the perimeter of the figure
Figure 1 = 1 x 2 + 7 = 9
Figure 2 = 2 x 2 + 7 = 11
Figure 3 = 3 x 2 + 7 = 13

Formula:
Perimeter of the figure = Pattern number x 2 + 7

Perimeter of figure 59
= 59 x 2 + 7
= 125

(c)
Figure number x 8 + 7 = 3671
Figure number x 8 = 3671 - 7 = 3664
Figure number = 3664 ÷ 8 = 458

Answer(s): (a) 143; (b) 125; (c) 458