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1/8" + 1/2"

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" + 1/2" =

=0-5/8"

Sum

0-5/8"

Decimal inch

0.625"

Millimetres

15.875 mm

1/8" − 1/2"

-0-3/8"

The work

Over a common denominator

Put both over 8: 1/8 = 1/8 and 1/2 = 4/8. Add the tops: 1/8 + 4/8 = 5/8. Reduced, that's 0-5/8" (0.625 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

1/8" to decimal 1/2" to decimal All fraction sums Add it on the calculator

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