Okay so I think I did this wrong (like I read the question wrong) but I think the lowest number of times you would have to swap the cards is 9. Like I said, not sure, so if you have the real answer please tell me because now I'm curious...
but I hope this helps somewhat!
I believe the answer is 5 mph east
Answer:
2.63905733
Step-by-step explanation:
Sorry I didn't round it
Formula

I got 36000000 . Hope this helps