3/4" + 13/16"
Adding two fractions of an inch, exactly — the everyday jobsite arithmetic that a decimal calculator gets wrong. Reduced, carried, and shown in millimetres.
3/4" + 13/16" =
=1-9/16"
Sum
1-9/16"
Decimal inch
1.5625"
Millimetres
39.6875 mm
3/4" − 13/16"
-0-1/16"
The work
Over a common denominator
Put both over 16:
3/4 = 12/16 and 13/16 = 13/16. Add the tops: 12/16 + 13/16 = 25/16, which carries past one inch. Reduced, that's 1-9/16" (1.5625 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.Keep going
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