For Step 1
Al's
k=1.50/6=1/4=0.25
Barbara's
k=3.12/13=0.24
Step 2
Al's
y=0.25x
Barbara's
y=0.24x
Step 3
Using the formula and the value of k we can calculate the missing value of the table
ears 6 14 21 200
cost $1.50 $3.50 $5.25 $50
ears 13 14 21 208
cost $3.12 $3.36 $5.04 $49.92
Step 4.
the constant of proportionality gives us the cost per ear
Step 5.
Barbar's has the better value because the constant of proportionality is a little low than Al's constant
