Ratios and Unit Rates with Fractions

Question

A box of cereal states that there are 90 calories in a 3/4​-cup serving. What is the unit rate for calories per​ cup? How many calories are there in 4 cups of the​ cereal?

Answer 1

A box of cereal states that there are 90 calories in a 3/4​-cup serving. What is the unit rate for calories per​ cup? How many calories are there in 4 cups of the​ cereal?

For this problem, we want to know how many calories are in 4 cups of cereal. The easiest way is to figure out the calories for 1 cup and multiply by 4. We know that there are 90 calories in 3/4 cup. To figure out how much is in 1/4 cup, divide 90 by 3 (to give the calories for 1/4 cup, then multiply by 4 to give the calories for 1 cup.

Once you have this answer, multiply by 4 to get the amount in 4 cups.

Answer 2

Unit rate = 90 / (3/4)

4 cups = unit rate * 4