Final answer:
To find the total number of apples in the box, we can set up a proportion. Solving the proportion, we find that there are 30 apples in the box.
Step-by-step explanation:
To find the total number of apples in the box, we can set up a proportion using the percentage given. We know that 30% of the total apples are rotten, so we can say that 30% is equivalent to 9 apples.
Let x represent the total number of apples. We can set up the proportion: (30/100) = (9/x).
To solve for x, we can cross multiply and then divide: (30/100) * x = 9. Simplifying this equation, we get: 0.3x = 9. Finally, divide both sides by 0.3 to find x: x = 9 / 0.3 = 30.
Therefore, there are 30 apples in the box (option A).