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1/8" + 9/16"

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" + 9/16" =

=0-11/16"

Sum

0-11/16"

Decimal inch

0.6875"

Millimetres

17.4625 mm

1/8" − 9/16"

-0-7/16"

The work

Over a common denominator

Put both over 16: 1/8 = 2/16 and 9/16 = 9/16. Add the tops: 2/16 + 9/16 = 11/16. Reduced, that's 0-11/16" (0.6875 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

1/8" to decimal 9/16" to decimal All fraction sums Add it on the calculator

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