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 10.
2. What is the perimeter of Figure 183?
3. Which figure requires a total number of 2399 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 10
= 10 x 8 + 7
= 87

(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 183
= 183 x 2 + 7
= 373

(c)
Figure number x 8 + 7 = 2399
Figure number x 8 = 2399 - 7 = 2392
Figure number = 2392 ÷ 8 = 299

Answer(s): (a) 87; (b) 373; (c) 299