If you bought 3 bags of popcorn from each company, how much would you save purchasing from PERFECT PICTURE POPCORN than from FANTASTIC FLICKS?

Determine the constant of proportionality (unit rate) per order of popcorn for each company.
Movie Company:
Movie mania
Fantastic Flicks
Perfect picture
The big screen

Constant of proportionality:

To determine the constant of proportionality (unit rate) per order of popcorn for each company, we need more information. Specifically, we need the prices of popcorn bags for each company.