93 miles ... 1 hour and 30 minutes = 90 minutes
x miles = ? ... 4 hours = 4 * 60 minutes = 240 minutes
If you would like to know how many miles can you drive in 4 hours, you can calculate this using the following steps:
93 * 240 = x * 90 /90
x = 93 * 240 / 90
x = 248 miles
Result: You can drive 248 miles in 4 hours.