To find out how far the airplane traveled, you can use the formula:
\[ \text{Distance} = \text{Speed} \times \text{Time} \]
In this case, the speed of the airplane is 600 kilometers per hour, and the time traveled is 4 hours. Plugging in the values:
\[ \text{Distance} = 600 , \text{km/h} \times 4 , \text{h} = 2400 , \text{km} \]
Therefore, the airplane traveled 2400 kilometers.