Here is how to convert 4.2 mm to inches. We will give you the fractional answer, the decimal answer, and illustrate the answer on our tape measure.
One millimeter is equal to 5/127 inches, and 4.2 as a fraction is 21/5. Therefore, to get the fractional answer to 4.2 mm in inches, we multiply 21/5 by 5/127 and simplify if necessary.
cm × 5/127 = inches
21/5 × 5/127 = inches
21/5 × 5/127 = 21/127
21/5 mm = 21/127 inches
4.2 mm = 21/127 inches
As promised above, we also have the answer to 4.2 mm in inches in decimal form. Although the fractional answer above is exact, the decimal answer may be rounded if necessary:
21/127 ≈ 0.165354330708661
21/127 ≈ 0.16535
4.2 mm ≈ 0.16535 inches
Our image below shows 4.2 mm on a tape measure. The top row of the tape measure is inches, and each mark on the bottom row is 1 millimeter (10 millimeter marks equal 1 centimeter).
As you can see, we drew a red line where 4.2 mm and 0.16535 inches meet on the measuring tape.
Millimeters to Inches Calculator
Here you can convert another length in millimeters to inches.
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