You have been asked to analyze the popcorn recipes of three different local theatres in order to figure out which theatre has the best popcorn. In this case, the "best" popcorn is the most buttery! In your quest to find the best, you meet with each theatre manager individually and ask for the ratio of oil to popcorn kernels that they use in their recipes. Here are their responses. The manager of Theatre A says that they usually go through about 15 cups of popcorn kernels and about 5 cups of oil each weeknight.
The manager of Theatre B says that they order 18 cups of oil and 72 cups of popcorn kernels each week.
The manager of Theatre C says that their concessions use 6 cups of oil and 32 cups of popcorn kernels on a busy Saturday.
You also ask about the amount of salt each theatre uses in their recipe. Their responses are below.

Theatre A uses 2 cups of salt for every 10 cups of oil.
Theatre B uses cup salt for every cup of oil.
Theatre C uses 1 cup of salt for every 6 cups of oil.
Theatre has the least buttery popcorn.