Answer
Jon's running rate is $\dfrac{1}{3}$ kilometers per minute.
Work Step by Step
Increase in Distance ran = $6-3=3$ km
Time duration = $9$ minutes
The running rate can be computed by dividing the increase in distance ran by the time:
Running Rate = $\dfrac{3\text{ km}}{9\text{ minutes}}=\dfrac{1}{3}$ kilometers per minute.