A rectangle has 6 seats around it (Figure 1). When arranged together, the rectangle has the following number of seats around it.
- How many seats are there if 12 rectangles are joined together?
- How many seats are there if 25 rectangles are joined together?
- Which figure has 338 seats together?
(a)
Pattern for the number of seats
Figure 1: 1 x 4 + 2 = 6
Figure 2: 2 x 4 + 2 = 10
Figure 3: 3 x 4 + 2 = 14
Pattern for the number of rectangles
Figure 1: 1
Figure 2: 2
Figure 3: 3
Number of rectangles = Figure number
Number of seats = Figure number x 4 + 2
Number of seats for 12 rectangles
= 12 x 4 + 2
= 50
(b)
Number of seats for 25 rectangles
= 25 x 4 + 2
= 102
(c)
Number of seats = Figure number x 4 + 2
Figure number = (Number of seats - 2) ÷ 4
Figure number
= (338 - 2) ÷ 4
= 336 ÷ 4
= 84
Answer(s): (a) 50; (b) 102; (c) 84