Answer:
The constant of proportionality gives you the price per unit at each store.
Step-by-step explanation:
If you assume that the price (y) is directly proportional to the amount (x) you get, the formula is
y = kx
where k is the constant of proportionality.
k = y/x
k has the units of cost per unit, for example, dollars per ounce.
The fewer the dollars per ounce, the better the deal you are getting.
If store A offers apple sauce at $1.29 for 25 oz and Store B offers apple sauce at $2.89 for 50 oz, which is the better deal?
At store A, k = $1.29/25 oz = $0.052/oz or 5.2¢/oz
At store B, k = $2.89/50 oz = $0.058/oz or 5.8¢/oz
The apple sauce is cheaper at Store A.
