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5/16" + 5/16"

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" + 5/16" =

=0-5/8"

Sum

0-5/8"

Decimal inch

0.625"

Millimetres

15.875 mm

5/16" − 5/16"

The work

Over a common denominator

Put both over 16: 5/16 = 5/16 and 5/16 = 5/16. Add the tops: 5/16 + 5/16 = 10/16. 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

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

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