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1/8" + 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.

1/8" + 3/4" =

=0-7/8"

Sum

0-7/8"

Decimal inch

0.875"

Millimetres

22.225 mm

1/8" − 3/4"

-0-5/8"

The work

Over a common denominator

Put both over 8: 1/8 = 1/8 and 3/4 = 6/8. Add the tops: 1/8 + 6/8 = 7/8. Reduced, that's 0-7/8" (0.875 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

1/8" to decimal 3/4" to decimal All fraction sums Add it on the calculator

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