# mean proportional

noun, Mathematics
1.
(between two numbers a and b) a number x for which a/x = x/b :
The number 3 is a mean proportional between 1 and 9.
Origin of mean proportional
1565-1575
1565-75
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the Web for mean proportional
Historical Examples
• The second of three numbers is a mean proportional between the other two.

Romeyn Henry Rivenburg
• Was his confounding two mean proportionals with one mean proportional found twice over a trick of the same intent?

Augustus de Morgan
• Each of the other sides is the mean proportional between the hypotenuse and the segment of the hypotenuse adjacent to that side.

David Eugene Smith
• We then find the mean proportional between the length HD and the height of the parallelogram.

Henry Ernest Dudeney
• Any diameter is a mean proportional between the transverse axis and the focal chord parallel to the diameter.

• Lastly, as there is only one mean proportional between each relation, there is also only one good government possible for a State.

Jean-Jacques Rousseau
• The perpendicular is the mean proportional between the segments of the hypotenuse.

David Eugene Smith
• In the Pyramid Cheops, altitude is very nearly a mean proportional between apothem and half base.

Robert Ballard
• Then x - 5 is a mean proportional between x - 9 and x, from which we find that x equals 25.

Henry Ernest Dudeney
• To find a mean proportional between two given straight lines.

### Difficulty index for mean proportional

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### Word Value for mean

6
8
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