Four quantities are in proportion when the ratio of the first to the second is equal to the ratio of the third to the fourth. An Elementary Geometry - Page 25by William Frothingham Bradbury - 1872 - 110 pagesFull view - About this book
| James Hamblin Smith - Arithmetic - 1878 - 390 pages
...=3x9, .'. number required = ^. = 5|. • 198. Three numbers are said to be in CONTINUED PROPORT1ON when the ratio of the first to the second is ' equal to the ratio of the second to the third. Thus 3, 6, 12, are in continued proportion, The second number is called a MEAN... | |
| James Maurice Wilson - 1878 - 450 pages
...consequents, B, Q. Def. 7. Three magnitudes (A, B, C) of the same kind are said to be proportionals, when the ratio of the first to the second is equal to that of the second to the third : that is when A : B :: B : C. In this case C is said to be the third... | |
| Benjamin Greenleaf - Algebra - 1879 - 376 pages
...all countries. The so-called French interpretation is not that of the modern French mathematicians. A PROPORTION is an equality of ratios. Four quantities...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 c : d, if equal to each other,... | |
| Benjamin Greenleaf - Algebra - 1879 - 322 pages
...countries. The so-called French interpretation i • not that of the modern French mathematicians. 303< A PROPORTION is an ,equality of ratios. Four quantities are in proportion when the ratio of the Jlrst to the second is the same as that of the third to the fourth. Thus, the ratios a : b and c :... | |
| James Thomson - 1880 - 408 pages
...Fonr numbers (or four numerics generally) constituting two equal ratios, and written in order so that the ratio of the first to the second is equal to the ratio of the third to the fourth (as, for instance 10, 15, 8, 12), are commonly called four proportionals. The first and last of the... | |
| Simon Newcomb - Geometry - 1881 - 418 pages
...a ratio gives us another definition of a proportion, namely: 354. Four magnitudes are proportional when the ratio of the first to the second is equal to the ratio of the third to the fourth. Thus the ratio B : A is the inverse of A : B. If A : B :: m : n, then A : B = - and B : A - - ; the... | |
| James Hamblin Smith - 1883 - 466 pages
...the other product must form the means. 358. Three quantities are said to be in CONTINUED PEOPOETION when the ratio of the first to the second is equal to the ratio of the second to the third. Thus a, b, c are in continued proportion if a : 6 = 6 : c. The quantity b is called... | |
| Edwin Pliny Seaver, George Augustus Walton - Algebra - 1881 - 304 pages
...7, how far from either shore will be their meeting-place ? 195. When three quantities are such that the ratio of the first to the second is equal to the ratio of the second to the third, the second quantity is called a mean proportional between the other two. Thus,... | |
| Mathematical association - 1883 - 86 pages
...consequents, B, Q. DEF. 7. Three magnitudes (A, B, C) of the same kind are said to be proportionals, when the ratio of the first to the second is equal to that of the second to the third : that is when A : B :: B : C. In this case C is said to be the third... | |
| Emerson Elbridge White - Arithmetic - 1883 - 370 pages
...Proportionals, and the last is the fourth proportional to the other three in their order. Three numbers are in proportion when the ratio of the first to the second equals the ratio of the second to the third ; as, 8:12:: 12:18. The second number is called a mean... | |
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