Some tables and chairs are arranged as shown:
- How many chairs are there in Figure 15?
- How many tables are needed for 56 chairs?
(a)
Pattern for the number of chairs
Figure 1: 1 x 2 + 2 = 4
Figure 2: 2 x 2 + 2 = 6
Figure 3: 3 x 2 + 2 = 8
Formula:
Number of chairs = Figure number x 2 + 2
Number of chairs for Figure 15
= 15 x 2 + 2
= 32
(b)
Pattern for the number of tables
Figure 1: 1
Figure 2: 2
Figure 3: 3
Formula:
Number of tables = Figure number
Figure number for 56 chairs
= (56 - 2) ÷ 2
= 54 ÷ 2
= 27
Number of tables = 27
Answer(s): (a) 32; (b) 27
