mean proportional

noun

Mathematics.

1. (between two numbers a andb ) a number x for which a/x = x/b .

   The number 3 is a mean proportional between 1 and 9.

Word History and Origins

Origin of mean proportional¹

First recorded in 1565–75

Example Sentences

One of the isothermal surfaces will be a sphere S surrounding the sink, which, however, will not be at the centre of the sphere, but so situated that the source, sink, and centre are in line, and that the radius of the sphere is a mean proportional between the distances of the source and sink from the centre.

Read more on Project Gutenberg

Define ratio, proportion, mean proportional, third proportional, fourth proportional.

Read more on Project Gutenberg

Find a mean proportional between 4 and 16; 18 and 50; and 3.

Read more on Project Gutenberg

The second of three numbers is a mean proportional between the other two.

Read more on Project Gutenberg

If 4 quantities are in proportion and the second is a mean proportional between the third and fourth, prove that the third will be a mean prop. between the first and second.

Read more on Project Gutenberg