If you have 9 completely identical beans, but one is slightly heavier. How do you find which bean is heavier with a scale that you can only use twice.

There are three identical boxes of apples and oranges, except one contains all apples, one contains all oranges, and one contains a mix. The boxes are labeled “apples”, “oranges”, and “apples and oranges” but all 3 boxes were labeled incorrectly! You have the opportunity to inspect fruit from the boxes one at a time, without looking inside the box. What is the fewest number of fruit you need to inspect to correctly label the contents of the identical boxes?