 | William Frothingham Bradbury - 1877 - 262 σελίδες
...; also the ratio of A : B and m A :mB. 5. Proportion is an equality of ratios. Four quantities are proportion when the ratio of the first to the second is equal in The equality of two ratios is indicated by the sign of equality (=), or by four dots (: :). Thus,... | |
 | James Hamblin Smith - 1878 - 390 σελίδες
...=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 σελίδες
...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 - 1879 - 350 σελίδες
...interpretation is 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 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,... | |
 | James Thomson - 1880 - 408 σελίδες
...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 - 1881 - 418 σελίδες
...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 σελίδες
...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 - 1881 - 304 σελίδες
...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,... | |
 | Emerson Elbridge White - 1883 - 370 σελίδες
...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... | |
 | Mathematical association - 1883 - 86 σελίδες
...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... | |
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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. 
