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5/8" + 11/16"

Adding two fractions of an inch, exactly — the everyday jobsite arithmetic that a decimal calculator gets wrong. Reduced, carried, and shown in millimetres.

5/8" + 11/16" =

=1-5/16"

Sum

1-5/16"

Decimal inch

1.3125"

Millimetres

33.3375 mm

5/8" − 11/16"

-0-1/16"

The work

Over a common denominator

Put both over 16: 5/8 = 10/16 and 11/16 = 11/16. Add the tops: 10/16 + 11/16 = 21/16, which carries past one inch. Reduced, that's 1-5/16" (1.3125 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

5/8" to decimal 11/16" to decimal All fraction sums Add it on the calculator

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