Question

The cost of buying shoes is shown in the table below

Answer 1

Part A

• The graph is attached

Part B

For zero number the cost is zero and the rate of change is 25.

• 0 - 0, 1 - 25, 2 - 50, 3 - 75, 4 - 100

This is the indication of the proportional relationship

Part C

• It is a constant change as the difference is same for each step - 25
• The ordered pair (1, 25) shows the unit rate is $25 per pair of shoes

Part D

• Constant of proportionality is 25

Part E

The equation is:

• y = 25x,

where y - cost, x - number of pairs of shoes, 25 - constant of proportionality