The metric system is used in many countries around the world, including Canada (as of 1970), France, Denmark, Norway and Italy. It is a more straightforward system of measurement than the American inchpound system. Ten millimeters are equal to one centimeter, for example, and 100 centimeters are equal to one meter. Compare this to the inchpound system in which 12 inches make a foot and three feet make a yard. Converting height in inches, feet, yards or miles to the metric system is simple once you learn the basic calculations.
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Multiply miles by 1.609 to obtain the height in kilometers. For example, something 12 miles high would be approximately 19.31 kilometers high.

Multiply yards by 0.9144 to obtain the height in meters. For example, something 12 meters high would be 10.9728 meters high.

Multiply feet by 0.3048 to obtain the height in meters. For example, something 12 feet high would be 3.6576 meters high.

Multiply inches by 2.54 to obtain the height in centimeters. For example, something 12 inches high would 30.48 centimeters high. Multiply inches by 25.4 to obtain the height in millimeters. For example, something 12 inches high would be 304.8 millimeters high.
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