How much ketchup and mustard for 300 people cookout?

For a cookout serving 300 people, a general guideline is to plan for about 1 ounce of ketchup and 1 ounce of mustard per person. This means you would need approximately 19 pounds of ketchup and 19 pounds of mustard. Adjust the quantities based on your guests' preferences, as some may use more condiments than others. Consider providing extra bottles for those who enjoy more toppings.