 Convert length units within and between measurement systems.

 Meter – basic unit of length in the metric system. Defined as 1 ten-millionth of the distance from the equator to either pole. Currently defined by the speed of light.  Meter = the distance light travels in 1/ of a second

 Basic unit is the foot 1 ft = 12 in 1 yd = 3 ft 1 mi = 5280 ft

 1 in = 2.54 cm  1 mi = 1.61 km  1 cm = in

 Conversion factor – an expression used to change from one unit or set of units to another. Derived from equivalent measures Equal to 1

 Change 4 m to cm  Change 39.5 mm to cm  Convert 84 in to ft  Express 60 in in cm  Change 15 mi to km  Convert 220 cm to in  Change 3 yd to cm