The ratio of the number of empty seats to the number of occupied seats can be found by dividing the two numbers. Here, there are 39 empty seats and 11 occupied seats. Therefore, the ratio is:

$\frac{\text{empty seats}}{\text{occupied seats}} = \frac{39}{11}$

So, the ratio of empty seats to occupied seats is $39:11$.

Would you like further details or have any questions?

Here are 5 related questions:

1. What would the ratio be if 5 more seats were occupied?
2. How can the ratio change if some passengers board or deboard the plane?
3. What is the total number of seats on the airplane?
4. How would you express the ratio as a fraction or decimal?
5. Can you simplify ratios like 39:11 further, and if so, how?

Tip: Ratios compare two quantities and can be expressed in different forms, such as fractions, decimals, or with a colon.