How many inches does 57mm equal?

Answer 1

When it comes to metric length conversions, there is only one scale to remember.

"One inch equals 2.54 centimeters." Learn it. It is not rounded off or estimated. It is like there being 12" in a foot or 100cm in a meter. It is exact.

With that knowledge, convert mm to cm and get 5.7cm

5.7 / 2.54 = 2.2" to 2 sigfigs◄

Also, using this fact as a springboard, you can determine the US units of size of a cube holding 1 liter of water by knowing that a liter is in a box 10cm on a side, and weighs 1kg

All three major scales can be computed from just the simple fact that 1" = 2.54cm■