The average tornado is 50 yards wide and travels 5 miles.
The Tri-State tornado was a mile wide and traveled 219 miles.
There isn't a specific distance because all of the tornadoes in the world are not the same. The typical tornado may travel a mile or so, but path lengths may range from only a few yards to more than 200 miles.
It depends on how fast the tornado is traveling. The average tornado moves at about 30 mph, so in 15 minutes an average tornado would move 7.5 miles. However, some tornadoes move much faster. The fastest moving tornado on record was found, at times, to travel at 73 mph. At that speed the tornado would travel just over 18 miles in 15 minutes.
An average tornado would probably be in the mid EF1 range with peak winds of 90 to 100 miles per hour. The tornadoes that make national news are usually much stronger.
The Joplin tornado traveled 22.1 miles.
The largest tornado on record was 2.6 miles wide. It traveled a distance of 16 miles near El Reno, OK on May 31, 2013. The longest tornado path on record was 219 miles from the Tri-State tornado of 1925. This, however, is a measure of distance traveled rather than size.
The Hallam, Nebraska tornado was 2.5 miles wide and traveled 54 miles.
The average tornado is 150 feet wide. Some, can be less than 30 feet wide however, and the very largest can be up to two and a half miles wide.
The distance a tornado travels varies considerably. A typical tornado travels only a mile or two. Some tornadoes will only bee on the ground for a few hundred feet. The worst tornadoes usually travel ten miles or more, with some paths being well over 100 miles long. The longest tornado track on record was 219 miles.
The average tornado lasts about 10 minutes.
The Waco, Texas tornado traveled 20 miles and was 1/3 of a mile wide.
~6 mi