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5/16" + 7/8"

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" + 7/8" =

=1-3/16"

Sum

1-3/16"

Decimal inch

1.1875"

Millimetres

30.1625 mm

5/16" − 7/8"

-0-9/16"

The work

Over a common denominator

Put both over 16: 5/16 = 5/16 and 7/8 = 14/16. Add the tops: 5/16 + 14/16 = 19/16, which carries past one inch. Reduced, that's 1-3/16" (1.1875 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

5/16" to decimal 7/8" to decimal All fraction sums Add it on the calculator

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