A rower wanted to determine the speed of a river's current prior to going down a particular section of the river.

She released a tracker into the river. The tracker sent her back the following information:

3 seconds after the tracker was released into the river, the tracker had traveled 7 meters.

10.7 seconds after the tracker was released into the river, the tracker had traveled 19.5 meters.

Assuming the river was flowing at a constant speed, what was the speed of the current on this section of the river?