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1/8" + 3/16"

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

1/8" + 3/16" =

=0-5/16"

Sum

0-5/16"

Decimal inch

0.3125"

Millimetres

7.9375 mm

1/8" − 3/16"

-0-1/16"

The work

Over a common denominator

Put both over 16: 1/8 = 2/16 and 3/16 = 3/16. Add the tops: 2/16 + 3/16 = 5/16. Reduced, that's 0-5/16" (0.3125 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

1/8" to decimal 3/16" to decimal All fraction sums Add it on the calculator

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