5/16" + 7/16"
Adding two fractions of an inch, exactly — the everyday jobsite arithmetic that a decimal calculator gets wrong. Reduced, carried, and shown in millimetres.
5/16" + 7/16" =
=0-3/4"
Sum
0-3/4"
Decimal inch
0.75"
Millimetres
19.05 mm
5/16" − 7/16"
-0-1/8"
The work
Over a common denominator
Put both over 16:
5/16 = 5/16 and 7/16 = 7/16. Add the tops: 5/16 + 7/16 = 12/16. Reduced, that's 0-3/4" (0.75 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.Keep going
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