Question

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A small bag of trail mix contains 3 cups of dried fruit and 4 cups of almonds. A large bag contains $4 1/2 cups of dried fruit and 6 cups of almonds. Write and solve a system of linear equations to find the price of 1 cup of dried fruit and 1 cup of almonds. Let f represent the price of one cup of dried fruit and let a represent the price of one cup of almonds.What is the equation for the small bag and the large bag.

Answer 1

Let's call:

f = price of 1 cup of dried fruit

a = price of 1 cup of almonds

In order to build the linear system, you need to consider that the total price of a bag is given by the sum of the price of cups times the number of cups in each bag, therefore:

Solve for a in first equation:

a = (6 - 3f) / 4

Then substitute in the second equation:

41/2 f + 6 · (6 - 3f) / 4 = 9

41/2 f + 9 - 9/2 f = 9

16 f = 0

f = 0

Now, substitute this value in the formula found for a:

a = (6 - 3·0) / 4

= 3/2 = 1.5

Hence, the cups of dried fruit are free and 1 cup of almond costs 1.5$

Explanation: