Four glasses of milk and 3 snack bars have a total of 83 carbohydrates​ , and 3 glasses of milk and 4 snack bars have a total of 85 carbs. Determine how many carbs are in one glass of milk

Answer 1

glasses of milk = M

snack bars = S

4M + 3S = 83

3M + 4S = 85

using substitution:

3M + 4S = 85

-3M from both sides

4S = 85 -3M

divide both sides by 4

S = (85 - 3M)/4

substitute into first equation

4M + 3 ( (85 - 3M) /4 ) = 83

multiply both sides by 4

16M + 3 (85 -3M) = 332

distribute the 3

16M + 255 - 9M = 332

combine like terms

7M + 255 = 332

subtract 255 from both sides

7M = 77

Divide both sides by 7

M = 11

each glass of mile has 11 carbs.