Convert from caliber to metric mile [high school]

Unit Definition (caliber)
The caliber is a unit used to express the bore diameter of a gun. Traditionally, the diameter is stated in inches, so that ".22 caliber" refers to a pistol having a bore of 0.22 inches (5.588 mm). So the caliber is actually equivalent to the inch. The usage of the term "caliber" is actually now in decline, because bore diameters of many guns are now stated in millimeters. "Caliber" is the American spelling; elsewhere the unit is often spelled "calibre."

Unit Definition (metric mile [high school])
A metric mile is a distance of 1,500 meters. This distance is used when it is desirable to approximate the statute mile, yet also desirable to use a convenient round number in SI or metric units. A statute mile is actually 1,609.347 meters.