Question

Four glasses of milk and 3 snack bars have a total of 96 carbohydrates (carbs), and 2 glasses of milk and 4 snack bars have

many carbs are in one glass of milk and in one snack bar,
total of 78 carbs. Determine how many carbs are in one glass of milk

Answer 1

Each snack bar contains 12 carbs and each milk contains 15 carbs.

Explanation:

Let M be the carbs in milk and S the carbs in a snack bar.

We are told:

4M + 3S = 96, and

2M + 4S = 78

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We can eliminate one of the variables and then solve for the other. Let's multiply the second equation by -2 and then add it to the first. This will eliminate the M:

4M + 3S = 96

-4M - 8S = -156

-5S = - 60

S = 12

Each snack bar has 12 carbs. Use either equation to find M. I'll use the second:

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2M + 4S = 78

2M + 4*(12) = 78

2M + 48 = 78

2M = 30

M = 15

Each milk contains 15 carbs