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3/8" + 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.

3/8" + 13/16" =

=1-3/16"

Sum

1-3/16"

Decimal inch

1.1875"

Millimetres

30.1625 mm

3/8" − 13/16"

-0-7/16"

The work

Over a common denominator

Put both over 16: 3/8 = 6/16 and 13/16 = 13/16. Add the tops: 6/16 + 13/16 = 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

3/8" to decimal 13/16" to decimal All fraction sums Add it on the calculator

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