You can't divide eight by four because then the answer would be two and all of the juice boxes would cost more if that was true. Instead, you have to divide 4 by 8 and that gives you 1/2 or one-half. In this case since it is money you have to figure out what half of a dollar is. A dollar is worth 100 cents and if you divide that in half you get fifty cents. Each juice box costs fifty cents.