The problem asks us to find the missing number in the division equation $285.9 \div \Box = 28.59$.

1. Problem Description

The problem asks us to find the missing number in the division equation $285.9 \div \Box = 28.59$.

2. Solution Steps

To find the missing number, we can divide $285.9$ by $28.59$.

$$\frac{285.9}{28.59} = \frac{2859}{285.9} \times \frac{10}{10} = \frac{2859}{2859} \times 10 = 10$$

Alternatively, we can think about how the decimal point shifted. The decimal point in $285.9$ moved one place to the left to become $28.59$. Dividing by 10 moves the decimal point one place to the left.

3. Final Answer

10