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5/8" + 15/16"

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

5/8" + 15/16" =

=1-9/16"

Sum

1-9/16"

Decimal inch

1.5625"

Millimetres

39.6875 mm

5/8" − 15/16"

-0-5/16"

The work

Over a common denominator

Put both over 16: 5/8 = 10/16 and 15/16 = 15/16. Add the tops: 10/16 + 15/16 = 25/16, which carries past one inch. Reduced, that's 1-9/16" (1.5625 inches). TapeMath tracks it as an exact fraction, so it lands dead on the tape mark.

Keep going

5/8" to decimal 15/16" to decimal All fraction sums Add it on the calculator

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