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→How does it work
== How does it work ==
== How does it work ==
Why does multiplication and division work on the C and D scales?
The multiplication of 100 by 1000 can be represented as 102 x 103 =105, to multiply, just add the indices, in this case, 2+3=5. 2 and 3 are the logarithms of 100 and 1000 respectively.
To multiply, add the logarithms, to divide, subtract. See how the C and D scales are compressed to their right end . Though the scales are marked with numbers, their distance along the scales are proportional to the logarithms of those numbers. When two distances are added, the logarithms of the marked numbers are added, if logarithms are added, numbers are multiplied.