For numbers 10-13, write an equation that represents the proportional relationship between total cost (c) and the number of items a person might buy (x), using the store that offers the best price. where would you buy each item? keep in mind that an equation allows someone to calculate the total cost of a particular grocery item no matter how many of that item is purchased. hint: the cost equation should have the variable ‘c’ and ‘x’ in it. 10a. which store has the best priced smooth cola 12-pack? * 1 point a) store 1 b) store 2 the price for the store is 3 for 10 and 5 for 15