A fast food company sells a #1 burger special for dinner. Each burger special cost 2.50 to make. The burger special sells for 10.50 each. The fast food company spends 400 on supplies. How many burger specials must the fast food company sell to break even?

the law of definite proportions states samples of a compound will always contain the same proportion of elements by mass. in other words, a given compound will always contain the same elements in the same proportions by mass.the law of multiple proportions states when two elements combine with each other to form more than one compound, then the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.