The nutritional chart on the side of a box of a cereal states that there are 93 calories in a three fourths 3/4 cup serving. how many calories are in 5 cups of the cereal?

The answer for this question will be 620 calories.
In this case, 3/4 cup= 93 calories and you need 5 cups. First you need to count calorie per cups, it would be 1 cup/(3/4 cup) * 93 calorie = 124 calorie/cup.
Then 5 cup of cereal would be 5*124 calorie= 620 calories.