In order to find miles per hour we must first change the time given to us (57.1 seconds) into hours. We will do this by first changing the seconds to minutes:
57.1 seconds / 60 = .952 minutes
Now we can change our minutes to hours:
.952 minutes / 60= .016 hours
Now to find miles per hour we divide the miles by our time:
1 mile / .016 hours = 63.04 mph
I hope this help you