Eight hot dogs and seven hot dog rolls cost $13.60 . Seven hot dogs and eight hot dog rolls cost $13.40. How much, in cents, is the positive difference of the costs of a hot dog and a hot dog roll?
+36916 Let x = hot dog price and y = roll price, then according to the question :
8x + 7y = 13.60 and
7x + 8y = 13.40
Now solve for x and y and then find the difference between them......there are multiple ways to do this
Let's subtract the first eqaution from the second one
7x-8x + 8y-7y = 13.40-13.60
-x +y = -.20 Multiply both sides by -1
or x-y = .20 The difference between a hot dog and a roll is .20
