3/4" + 3/4"
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" + 3/4" =
=1-1/2"
Sum
1-1/2"
Decimal inch
1.5"
Millimetres
38.1 mm
3/4" − 3/4"
0"
The work
Over a common denominator
Put both over 4:
3/4 = 3/4 and 3/4 = 3/4. Add the tops: 3/4 + 3/4 = 6/4, which carries past one inch. Reduced, that's 1-1/2" (1.5 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.Keep going
The same math, offline
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