How many calories are in 30 grams of carbohydrates?

To determine the number of calories in carbohydrates, it's essential to know that each gram of carbohydrate provides approximately four calories. Therefore, when calculating the caloric content of 30 grams of carbohydrates, you multiply the number of grams by the caloric value per gram.

In this case:

30 grams × 4 calories/gram = 120 calories.

The number of calories derived from 30 grams of carbohydrates is accurately calculated as 120 calories. Thus, the understanding of basic macronutrient caloric values is critical in determining the correct answer.