A mathematical conversion formula uses conversion equivalents of like units to obtain the desired unit of measurement. By doing so, the conversion equivalents of like units cancel each other out. Once the like units are canceled, the remaining unit of measurement is the desired conversion.
To convert millimeters to feet and inches, first convert millimeters to inches then feet. The conversion formula is X multiplied by (Y divided by X) multiplied by (Z divided by Y), where X is millimeters, Y is inches and Z is feet.
First, substitute any given measurements for the corresponding letters in the formula. Next, perform any needed multiplication or division. Finally, round your answer to the nearest tenth to get the answers in feet and inches.
To see the formula in action, here is an example of converting 500 mm to feet and inches. The conversion equivalent of 1 mm is 0.03937 inches. Substitute the appropriate conversion equivalents into the formula: 500 mm multiplied by (0.03937 inches divided by 1 mm) multiplied by (1 foot divided by 12 inches) equals 1.6404 feet, or 1 foot 6 inches.
Round the decimal to the nearest tenth, the first number to the right of the decimal point. This makes it easy to convert the answer to feet and inches. When rounding, if the number to the right of the targeted number is greater than five, round the targeted number up by one digit. However, if the number is less than five, round the targeted number down by one digit.
Being comfortable with using basic math skills is the key to using the conversion formula. Knowing the conversion equivalent of millimeters in inches is the first step in converting millimeters to feet and inches. After that, it's just a matter of substituting the appropriate numbers for the corresponding letters in the formula.