to be for real i truly don't know but first you need to make the units the same and that's called renaming the you subtract
customary units of length is yards,feet,miles,and inches
inches are the answer
It depends on what you consider to be "customary" and what you wish to convert them to.
inches in customary units
A length is measured in millimeters then centimeters , meters and kilometers.
10 1/2
centimeters or cm in the metric system or SI and in the customary inches or in.
17.42 meters into customary units
In the SI system (metric), length is a meter, mass is the kilogram, and time is the second.
Metric
Measure to the nearest inch 1-2 inch1-4 and inch
What should you do to change a value in SI units to a value in U.S. customary units?