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7/16" + 7/8"

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

7/16" + 7/8" =

=1-5/16"

Sum

1-5/16"

Decimal inch

1.3125"

Millimetres

33.3375 mm

7/16" − 7/8"

-0-7/16"

The work

Over a common denominator

Put both over 16: 7/16 = 7/16 and 7/8 = 14/16. Add the tops: 7/16 + 14/16 = 21/16, which carries past one inch. Reduced, that's 1-5/16" (1.3125 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

7/16" to decimal 7/8" to decimal All fraction sums Add it on the calculator

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