 | Charles Davies - Arithmetic - 1847 - 368 pages
...This relation between four numbers is called proportion ; and generally, Four numbers are said to be in proportion when the ratio of the first to the second is the same as that of the third to the fourth. Hence, 181. How do you determine what part one number... | |
 | Elias Loomis - Conic sections - 1849 - 252 pages
...consequent; if equal, equal; and if less, less. Def. 3. 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; thus, if A, B, and C are in proportion, then A : B : : B : C. In this case the... | |
 | William Frederick Greenfield - 1853 - 228 pages
...product of the extremes is equal to that of the meam, and conversely. Four numbers are proportionals when the ratio of the first to the second is equal to that of the third to the fourth. Hence these ratios must be compared, which is effected by comparing... | |
 | William Somerville Orr - Science - 1854 - 534 pages
...is of course the same as the ratio 4 : 2, or the ratio 2:1. When there are four quantities such that the ratio of the first to the second is equal to the ratio of the third to the fourth, the four quantities are said tobe in proportion: thus, if the four quantities a, b, c, d, be euch that... | |
 | Barnard Smith - Arithmetic - 1854 - 368 pages
...and thus those numbers are proportionals. 149. When proportion exists among four numbers, that is, when the ratio of the first to the second is equal to that of the third to the fourth, this proportion or equality is often denoted by writing down the two... | |
 | 1855 - 424 pages
...that the first divided by the second is equal to the third divided by the fourth — in other words, when the ratio of the first to the second is equal to the ratio of the third to the fourth, the four are said to be in direct proportion. From this definition it will be seen, that proportion... | |
 | Charles Davies - Algebra - 1857 - 408 pages
...remains the same, while a and b undergo changes of value, then a is said to be proportional to 6. 183i four quantities are in proportion, when the ratio...is equal to the ratio of the third to the fourth. Thus, if b_ d_ ~^~~' the quantities a, b, c and d, are said to be in proportion. We generally express... | |
 | Benjamin Greenleaf - Arithmetic - 1857 - 452 pages
...?^ t" Ans. 82m. 2fur. 20rd. PROPORTION. 332. A PROPORTION is an equality of ratios. Any four numbers 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 9 : 3 and 6 : 2, being equal to each... | |
 | Elias Loomis - Conic sections - 1858 - 256 pages
...consequent ; if equal, equal ; and if less, less. Def. 3. 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 ; thus, if A, B, and C are in proportion, then A : B : : B : C. In this case the... | |
 | Benjamin Greenleaf - Arithmetic - 1858 - 458 pages
...? Ans. 82m. 2fur. 20rd 7mA PROPORTION. 332, A PROPORTION is an equality of ratios. Any four numbers 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 9 : 3 and 6 : 2, being equal to each... | |
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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. 
