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9/16" + 11/16"

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

9/16" + 11/16" =

=1-1/4"

Sum

1-1/4"

Decimal inch

1.25"

Millimetres

31.75 mm

9/16" − 11/16"

-0-1/8"

The work

Over a common denominator

Put both over 16: 9/16 = 9/16 and 11/16 = 11/16. Add the tops: 9/16 + 11/16 = 20/16, which carries past one inch. Reduced, that's 1-1/4" (1.25 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

9/16" to decimal 11/16" to decimal All fraction sums Add it on the calculator

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