It looks like 82 grams of Fruity Pebbles – the amount you might be inclined to pour into your cereal bowl – is about 2 cups of cereal. This is a lot more than the standard 3/4 recommended serving size.
Read about how consumption of breakfast cereals like Fruity Pebbles contributes to American consumption of excess sugar in Musings on Sugar Consumption and Fruity Pebbles.