3 1/2 = 7/2 miles ... 3/4 hour = 3/4 * 60 minutes = 45 minutes
x miles = ? ... 1 minute
y miles = ? ... 1 hour
If you would like to know the number of miles in 1 minute or the number of miles in 1 hour, you can calculate this using the following steps:
7/2 * 1 = 3/4 * y
7/2 = 3/4 * y /*4/3
y = 7/2 * 4/3
y = 14/3 = 4 2/3 miles (per one hour)
7/2 * 1 = 45 * x
7/2 = 45 * x /45
x = 7/2 / 45
x = 7/90 miles (per one minute)