This is part one of a math poser.
You have a sandwich shop. They offer subs, pizzas, and (oddly enough) whole watermelons.
Each of these food items comes in two sizes: the small (six inch), and the large (12 inch) sizes. With the watermelons its the radius of a perfectly spherical shaped watermelon.
Every now and then this deli has a sale in which they offer X number of the small size for the price of one of the large size.
My question is this: at what number of the small sized units for the price of one big unit does the offer become a "good deal"?
We will start with the submarine sandwiches.
Check all quantities of small subs in which it is a good deal to buy them all for the price of one big one.
Explain your reasoning.