For 4 people, the typical amount of dry rice needed is about 1 cup, which will yield approximately 3 cups of cooked rice. This is based on the guideline that a serving size of cooked rice is generally around 3/4 cup to 1 cup per person, depending on whether it is a side dish or the main part of the meal. If rice is the main dish or guests have larger appetites, you may want to use slightly more, around 1/4 cup dry rice per person or a bit more. Generally, 1 cup of dry rice should be sufficient for four average adult servings.