ratio

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ratio.

The ratio of two quantities expressed in terms of the same unit is the fraction that has the first quantity as numerator and the second as denominator. For example, if in a group of 100 people 5 die, the ratio of deaths to the total number in the group is 5/100=1/20=.05. Ratios are indicated also by writing the two values with a colon between them, e.g., the ratio of 4 to 8 can be expressed by 4:8 as well as by 4/8.

Ratio

A relationship in magnitude, quantity, or degree between two or more similar things.

Ratio

 

The ratio of two numbers is the quotient from the division of the first number, by the second. The ratio of two homogeneous magnitudes is the number obtained by measuring the first magnitude when the second is chosen as the unit of measurement. If two magnitudes are measured in the same unit of measurement, their ratio is equal to that of the numbers that measure them.

The ratio of the lengths of two segments may be expressed by a rational or irrational number. In the former case the segments are said to be commensurable, and in the latter incommensurable. Mathematicians of the ancient world had no knowledge of irrational numbers. For them the concept of the ratio of two segments did not reduce to the concept of number. In their conception the geometrical theory of the ratios of magnitudes was not connected with the concept of number and played an independent role. In a sense, it substituted for a theory of real numbers. Indeed, according to Euclid the four segments, a, b, a’, and b’ form the proportion a: b = a’:b’ if for any natural numbers m and n one of the relations ma = nb, ma > nb, ma < nb is satisfied simultaneously with the corresponding relation ma’ = nb’, ma’> nb’, or ma’ < nb’. It follows that when a and b are incommensurable the subdivision of the rational numbers (x = m/n) into two classes according to whether a > xb or a < xb coincides with the subdivision according to whether a’ > xb’ or a’ < xb’ —this is the idea behind the modern theory of Dedekind cuts.

ratio

[′rā·shō]
(mathematics)
A ratio of two quantities or mathematical objects A and B is their quotient or fraction A / B.

ratio

Maths a quotient of two numbers or quantities
References in periodicals archive ?
Table-I: Comparison of preoperative and postoperative functional class, cardiothoracic ratio and echocardiography parameters.
Keywords: Chest radiography, echocardiography, cardiothoracic ratio, aortic regurgitation, mitral regurgitation, children
One of the methods used to quantify the heart size on chest radiography is the cardiothoracic ratio (1).
The cardiothoracic ratio was measured as described by Danzer (1): A vertical line is drawn on the frontal film through the spinous procardiac enlargements of the vertebrae.
7) demonstrated that, although there was good correlation between the radiographic total cardiac volume and echocardiographic ventricular volumes, especially for left-sided lesions in children, cardiothoracic ratio and cardiac frontal area did not correlate with echocardiographic measurements.
Relationship of cardiothoracic ratio and plain film heart volume to late survival.