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1/2" + 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.

1/2" + 3/4" =

=1-1/4"

Sum

1-1/4"

Decimal inch

1.25"

Millimetres

31.75 mm

1/2" − 3/4"

-0-1/4"

The work

Over a common denominator

Put both over 4: 1/2 = 2/4 and 3/4 = 3/4. Add the tops: 2/4 + 3/4 = 5/4, which carries past one inch. Reduced, that's 1-1/4" (1.25 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

1/2" to decimal 3/4" to decimal All fraction sums Add it on the calculator

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