40,000 feet equates to approximately 7.58 miles.
5280 feet = 1 mile40000 feet = 40000/5280 = 7.57576 miles (5dp)
5280 feet = 1 mile30000 feet / 5280 feet = 5.682 miles (rounded to third decimal).
3,209 feet = 0.608 miles.
I mile = 5,280 feet. So 1,000 feet is about 1/5 mile.