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1/4" + 15/16"

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

1/4" + 15/16" =
=1-3/16"
Sum
1-3/16"
Decimal inch
1.1875"
Millimetres
30.1625 mm
1/4" − 15/16"
-0-11/16"
The work

Over a common denominator

Put both over 16: 1/4 = 4/16 and 15/16 = 15/16. Add the tops: 4/16 + 15/16 = 19/16, which carries past one inch. Reduced, that's 1-3/16" (1.1875 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.
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