Question

Two glasses of milk and 3 snack bars have a total of 61 carbohydrates​ (carbs), and 4 glasses of milk and 2 snack bars have a total of 70 carbs. Determine how many carbs are in one glass of milk and in one snack bar.

Answer 1

24 carbohydrates

Explanation:

Represent Snack bars with S and Milks with M.

So, we have:

`2M\ and\ 3S\ = 61`

and

`4M\ and\ 2S\ = 70`

Required: Solve for M and S

Convert the given expressions to mathematical expressions:

`2M + 3S = 61` --- (1)

`4M + 2S = 70` --- (2)

Multiply the first equation by 2

`2M + 3S = 61` --------- * 2

`4M + 6S = 122` --- (3)

Subtract (1) from (3)

`4M - 4M + 6S - 2S = 122 - 70`

`4S = 52`

Solve for S

`S = 52/4`

`S = 13`

Substitute 13 for S in (2)

`4M + 2S = 70`

`4M + 2 * 13 = 70`

`4M + 26 = 70`

Solve for 4M

`4M = 70 - 26`

`4M = 44`

Solve for M

`M = 44/4`

`M = 11`

1 glass of milk and 1 snack bar = S + M

`S + M = 13 + 11`

`S + M = 24`