Question

A box of cereal states that there are 75 calories in a 34-cup serving. What is the unit rate for calories per cup? How many calories are there in 4 cups of the cereal?

Answer 1

The unit rate is how many calories are in 1 cup of cereal.
Set up a proportion:
$\frac{75 cal}{3/4 cup} = \frac{X cal}{1 cup}$
Cross multiply and solve:
$\frac{3}{4} X = 75\\ 3X=300\\X=100$
There are 100 calories per cup of cereal.

To get the calories in 4 cups of cereal, simply multiply the unit rate of 100cals/cup by 4.
$100*4=400$
There are 400 calories in 4 cups of cereal.

Answer 2

Who is eating 34 cups of cereal?! 75 calories! seriously!