To find the missing number, we can set up the equation based on the information provided:
Let \( x \) be the missing number. We know that 30% of \( x \) is equal to 2,400. We can express this mathematically as:
\[ 0.30 \times x = 2,400 \]
Now, to solve for \( x \), we divide both sides by 0.30:
\[ x = \frac{2,400}{0.30} \]
Calculating the right side:
\[ x = \frac{2,400}{0.30} = 2,400 \div 0.30 = 8,000 \]
Therefore, the missing number is \( \boxed{8,000} \).