Coffee with sugar and milk added to it can contain up to calories. To consume a maximum of 600 mg if caffeine per day, how many
full eight-ounce servings of a name-brand coffee with 330 mg of caffeine per 16-ounce serving could someone drink in a day and still stay below this limit? full 8-ounce servings
We know there is 330 mg of caffeine per 16-ounce serving. So if we want 8-ounce servings: 330 mg : 2 = 165 mg Also we have to consume a maximum of 600 mg. 165 mg * 3 = 495 mg < 600 mg 165 mg * 4 = 660 mg > 600 mg Answer: Someone could drink 3 full 8-ounce servings in a day and still stay below the limit.
Their error is in step 2. They added three to each number in (3y+8) instead of distributing it with multiplication. The correct step would be 9y-24=10y+3
