11/2 miles in 15 minutes = 6 mph
680 mph
15 mph
It equates to about 25 miles per hour.
6.4mph
You must drive at a speed of (16.9 miles) per (15 minutes), or 67.6 mph.
64 miles/hr
80 miles per hour.
15 miles in 225 minutes = 1 mile in 15 minutes = 4 miles per hour
20 mph
160 mph.
120 mph