The Math Team sells crunchy and fruity trail mixes to raise money. The ratio of fruit to nuts in each mix and the price they charge for an 8-oz (or -cup) bag of each mix are given in the table below. [Hint: The ratio of fruit to nuts in the crunchy trail mix is 1:3. So, of each bag is fruit and of each bag is nuts.] Ratio of fruit to nuts Price of an 8-oz (or cup) bag
Crunchy trail mix 1:3 $2.50
Fruity trail mix 5:3 $3.50
They have 30 cups of fruit and 50 cups of nuts to use in their trail mixes. So, they need to know how many bags of each type of mix they should they make. They let c represent the number of bags of crunchy trail mix and f represent the number of bags of fruity trail mix. Which set of inequalities below represents the conditions?

a. 0.25c + 0.625f ≤ 60
0.75c + 0.375f ≤ 100
c ≥ 0, f ≥ 0

b. 1c + 3 f ≤ 30
5c + 3 f ≤ 50
c ≥ 0, f ≥ 0

c. 1c + 5 f ≤ 60
3c + 3 f ≤ 100
c ≥ 0, f ≥ 0

d. 0.25c + 0.625f ≤ 30
0.75c + 0.375f ≤ 50
c ≥ 0, f ≥ 0