Math Help Please!

Question

A store owner want to develop a new snack mix by mixing chocolate and trail mix. How many pounds of chocolate costing $8.10 per pound should be mixed with 13 pound of trail mix costing $3.20 per pound to create a mixture worth $5.55. (round to the nearest pound)

Answer 1

8.1X + 3.2(13) = 5.55(X+13)

8.1X + 41.6 = 5.55X + 72.15

(8.1 - 5.55)X = 72.15-41.6

2.55X = 30.55

X = 30.55/2.55 = about 11.98 or 12 pounds

You want 5.55, by mixing 8.1 and 3.2

8.1- 5.55 = 2.55

5.55-3.2 = 2.35

3.2 is slightly closer to 5.55 than 8.1 is

so you want slightly more 3.2, slightly less 8.1

12 is slightly less than 13, so the answer looks about right

Had the mixture been exactly in between the two you would have wanted exactly the same amount of each.