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3/8" + 11/16"

Adding two fractions of an inch, exactly — the everyday jobsite arithmetic that a decimal calculator gets wrong. Reduced, carried, and shown in millimetres.

3/8" + 11/16" =
=1-1/16"
Sum
1-1/16"
Decimal inch
1.0625"
Millimetres
26.9875 mm
3/8" − 11/16"
-0-5/16"
The work

Over a common denominator

Put both over 16: 3/8 = 6/16 and 11/16 = 11/16. Add the tops: 6/16 + 11/16 = 17/16, which carries past one inch. Reduced, that's 1-1/16" (1.0625 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.
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