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3/8" + 3/8"

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" + 3/8" =

=0-3/4"

Sum

0-3/4"

Decimal inch

0.75"

Millimetres

19.05 mm

3/8" − 3/8"

The work

Over a common denominator

Put both over 8: 3/8 = 3/8 and 3/8 = 3/8. Add the tops: 3/8 + 3/8 = 6/8. Reduced, that's 0-3/4" (0.75 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

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

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