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3/8" + 3/4"

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" + 3/4" =

=1-1/8"

Sum

1-1/8"

Decimal inch

1.125"

Millimetres

28.575 mm

3/8" − 3/4"

-0-3/8"

The work

Over a common denominator

Put both over 8: 3/8 = 3/8 and 3/4 = 6/8. Add the tops: 3/8 + 6/8 = 9/8, which carries past one inch. Reduced, that's 1-1/8" (1.125 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

3/8" to decimal 3/4" to decimal All fraction sums Add it on the calculator

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