| Charles Davies, William Guy Peck - Mathematics - 1859 - 622 pages
...the ini'asure of proportion is ratio. Four quantities are in proportion when the ratio of the lir.st **to the second is equal to the ratio of the third to the fourth** ; this relation is expressed algebraically thus, a. : b : : с : d. This expression is called a proportion... | |
| Charles Davies - Algebra - 1860 - 412 pages
...changes of value, then a is said to be proportional to b. • 183i 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.** Thus, if the quantities a, 6, c and d, are said to be in propoition. We generally express that these... | |
| Henry G C. Smith - 1863 - 200 pages
...term, 16, is called the Antecedent, and the second, 8, the Consequent. Pour numbers are said to be **Proportional when the ratio of the first to the second...is equal to the ratio of the third to the fourth.** On examining the four numbers, 14, 8, 35, 20, we find V = i5, or 14 : 8 = 85 : 20, and say 14 is to... | |
| 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
...is £ or f , &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... | |
| 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... | |
| James Hamblin Smith - 1869 - 412 pages
...the other product must form the means. 328. Three quantities are said to be in CONTINUED PROPORTION **when the ratio of the first to the second is equal to the ratio of the** second to the third. Thus a, b, с are in continued proportion if a : b = b : c. . The quantity b is... | |
| Richard Wormell - Geometry, Plane - 1870 - 304 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... | |
| James Hamblin Smith - Algebra - 1870 - 478 pages
...the other product must form the means. 358. Three .quantities are said to be in CONTINUED PBOPOKTION **when the ratio of the first to the second is equal to the ratio of the** second to the third. Thus a, 6, c are in continued proportion if a : b=b :c. Four quantities are said... | |
| Elias Loomis - Geometry - 1871 - 302 pages
...consequent ; if equal, equal ; and if less, less. Def. 3. Three quantities are said to be proportional, whey **the ratio of the first to the second is equal to the ratio of** th<i second to the third ; thus, if A, B, and C are in proportion then A : B : : B : C. In this case... | |
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