| Benjamin Greenleaf - Geometry - 1863 - 504 pages
...and C : D is AC AX C BX D' °r BX D' 125. A PROPORTION is an equality of ratios. Four magnitudes are in proportion, when the ratio of the first to the second is the same as that of the third to the fourth. Thus, the ratios of A : B and X : Y, being equal to i... | |
| Benjamin Greenleaf - 1863 - 338 pages
...of the modern French mathematicians. 303. A PROPORTION is an equality of ratios. Four quantities are in proportion when the ratio of the first to the second is the same as that of the third to the fourth. Thus, the ratios a : b and с : d, if equal to each other,... | |
| John Purdue Bidlake - Arithmetic - 1866 - 232 pages
...the numbers composing them are said tobe in proportion. In other words, " Four quantities or numbers are said to be in proportion when the ratio of the first to the second, is the same ns the ratio of the third to the fourth." Thus, the ratios of 8 to 16, and 24 to 48 being... | |
| 1872 - 398 pages
...8. 15. On comparing Def. 3 with Def. 1, it will be seen that when four quantities are in proportion, the ratio of the first to the second is equal to the ratio of the third to the fourth. Hence we may denote a proportion thus — 3:4 = 6:8 which is read — the ratio 3 to 4 is equal to... | |
| Gerardus Beekman Docharty - Geometry - 1867 - 474 pages
...&c. 79. Proportion is an equality of ratios. Thus, 80. Three quantities are said to be proportional when the ratio of the first to the second is equal to the ratio of the second to the third. As of the three quantities A (2), B (4), C (8), where f=f —^, both the same... | |
| William Thomas Brande, George William Cox - Encyclopedias and dictionaries - 1867 - 1090 pages
...tho equality or similitude of ratios ; four numbers or magnitudes being said to be proportional, or in proportion, when the ratio of the first to the second is the same as the ratio of the third to the fourth, or when the first divided by the second gives the... | |
| William Thomas Brande, George William Cox - Encyclopedias and dictionaries - 1867 - 1090 pages
...numbers or magnitudes being Scripture, a preacher. (Liddell and Scott, I said to be proportional, or in proportion, when the ratio of the first to the second is the same as the ratio of the third to the fourth, or when the first divided by the Ftcond gives the... | |
| William Frothingham Bradbury - Algebra - 1868 - 264 pages
...•; = -, or 6 : a. ao aba 195. PROPORTION is an equality of ratios. Four quantities are proportional when the ratio of the first to the second is equal to the ratio of the third to the fourth. The equality of two ratios is indicated by the sign of equality (=) or by four dots (: :). Thus, a : b... | |
| Richard Wormell - Geometry, Modern - 1868 - 286 pages
...trouble ourselves to inquire what this unit is. Four lines are in proportion, or are proportionals, when the ratio of the first to the second is equal to the ratio of the third and fourth. Very simple geometrical constructions enable us, as we shall see, to draw four straight... | |
| Benjamin Greenleaf - Geometry - 1868 - 340 pages
...and C : D is ACAXC BX D' °r BX D' 125. A PROPORTION is an equality of ratios. Four magnitudes are in proportion, when the ratio of the first to the second is the same as that of the third to the fourth. Thus, the ratios of A,: B and X : Y, being equal to A... | |
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