Question

4 glasses of milk and 2 snack bars have a total of 80 carbohydrates​ (carbs), and 2 glasses of milk and 3 snack bars have a total of 68 carbs. Determine how many carbs are in one glass of milk and in one snack bar

Answer 1

The amount of carbs in 1 glass of milk = 13 carbs

The amount of carbs in 1 snack bar = 14 carbs

Explanation:

Let us assume the carbs in 1 glass of milk = m

And the number of carbs in 1 snack bar = n

Now, total carbs in 4 glass of milk = 4 x (Carbs in 1 glass of milk) = 4 m

Also, total carbs in 2 snack bars = 2 x (Carbs in 1 snack bar) = 2 n

Here, Total carbs in 4 milk glass + 2 snack bar = 80

⇒ 4 m + 2 n = 80 .... (1)

Again, total carbs in 2 glass of milk = 2 x (Carbs in 1 glass of milk) = 2 m

Also, total carbs in 3 snack bars = 3 x (Carbs in 1 snack bar) = 3 n

Here, Total carbs in 2 milk glass + 3 snack bar = 68

⇒ 2 m + 3 n = 68 .... (2)

Now, solving both the given equations by ELIMINATION, we get:

4 m + 2 n = 80

2 m + 3 n = 68 x (-2)

we get the new set of equitation as:

4 m + 2 n = 80

- 4 m - 6 n = -136

Adding both equation, we get

- 4 n = -56

or, n = 56 /4 =14

Now, 4 m + 2 n = 80

So, 4 m = 80 -2 (14) = 80 - 28 = 52

⇒ m = 52/4 = 13

Hence, the amount of carbs in 1 glass of milk = m = 13 carbs

And the amount of carbs in 1 snack bar = n = 14 carbs