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3/16" + 13/16"

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

3/16" + 13/16" =

=1"

Sum

Decimal inch

Millimetres

25.4 mm

3/16" − 13/16"

-0-5/8"

The work

Over a common denominator

Put both over 16: 3/16 = 3/16 and 13/16 = 13/16. Add the tops: 3/16 + 13/16 = 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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3/16" to decimal 13/16" to decimal All fraction sums Add it on the calculator

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