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5/16" + 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.

5/16" + 11/16" =

=1"

Sum

Decimal inch

Millimetres

25.4 mm

5/16" − 11/16"

-0-3/8"

The work

Over a common denominator

Put both over 16: 5/16 = 5/16 and 11/16 = 11/16. Add the tops: 5/16 + 11/16 = 16/16. Reduced, that's 1" (1 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

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

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