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1/8" + 1/4"

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" + 1/4" =

=0-3/8"

Sum

0-3/8"

Decimal inch

0.375"

Millimetres

9.525 mm

1/8" − 1/4"

-0-1/8"

The work

Over a common denominator

Put both over 8: 1/8 = 1/8 and 1/4 = 2/8. Add the tops: 1/8 + 2/8 = 3/8. Reduced, that's 0-3/8" (0.375 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

1/8" to decimal 1/4" to decimal All fraction sums Add it on the calculator

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