There are 5280 feet in one mile. Therefore, 900 feet is equal to 900/5280 = 0.17045 recurring (that is, 0.170454545..) miles.
There are 1609.344 metres in one mlie. Therefore, rounded to three significant figures, 900 metres is equal to 900/1609.344 = 0.559 miles.
900 km = 562 miles approx.
900 mi. = 1,448.409 km
There are 1760 yards in one mile. Therefore, 900 yards is equal to 900/1760 = 0.51136 recurring (that is, 0.511363636..) miles.