Books Books
Conversely, if the product of two quantities is equal to the product of two other quantities, the first two may be made the extremes, and the other two the means of a proportion.
University Algebra: Embracing a Logical Development of the Science, with ... - Page 230
by Charles Davies - 1870

## An Introduction to Algebra: Being the First Part of a Course of Mathematics ...

Jeremiah Day - Algebra - 1814 - 304 pages
...=-jtyeducing the fractions, ad=bc. Thus 12: 8:: IS: 10, therefore 12x10=8x15. 375. On the other hand, if the product of two quantities is equal to the product of two others, the four quantities will form a proportion, when they are so arranged, that those .on one side...

## An Introduction to Algebra: Being the First Part of a Course of Mathematics ...

Jeremiah Day - Algebra - 1827 - 352 pages
...is, in both cases the same. And if no : b'. '.x : yy then a : b'.'.x : ny. 375. On the other hand, if the product of two quantities is equal to the product of two others, the four quantities will form a proportion, when they are so arranged, that those on one side...

## Elements of Algebra

Algebra - 1838 - 372 pages
...other that AxD=B*C, i „ , , BD we shall also have ~T=~r' A. O and hence, A : B : : C : D; that is, if the product of two quantities is equal to the product of two other quantities, two of them may be made the extremes, and the other two the means of a proportion. 180. If we have...

## First Lessons in Algebra: Embracing the Elements of the Science

Charles Davies - Algebra - 1839 - 272 pages
...each other that AxD=BxC, we shall also have — =— ; A. L> , and hence, A : B : : C : D. That is : If the product of two quantities is equal to the product of two other quantities, two of them may be made the extremes, and the other two the means of a proportion. Thus, if we have...

## Elements of Algebra

Bourdon (M., Louis Pierre Marie) - Algebra - 1839 - 368 pages
...so related to each other that we shall also have — =— , AC/ and hence, A : B : : C : D; that is, if the product of two quantities is equal to the product of two otter quantities, two of them may be made the extremes, and the other two the means of a proportion....

## First Lessons in Algebra: Embracing the Elements of the Science

Charles Davies - Algebra - 1840 - 264 pages
...each other that ta.ll.!! BD we shall also have — =— ; AO and hence, A : B : : C : D. That is : If the product of two quantities is equal to the product of two otlier quantities, two of them may be made the extremes, and the other two the means of a proportion....

## An Elementary Treatise on Algebra: For the Use of Students in High Schools ...

Thomas Sherwin - Algebra - 1841 - 314 pages
...transposition we obtain a — b = c — d. Therefore, if the+sum of two quantities is equal to the sum of two other quantities, the first two may be made the means, and the last two the extremes, or the reverse, of an equidifference. When three quantities, a, b, c, either...

## Elementary Algebra: Embracing the First Principles of the Science

Charles Davies - Algebra - 1842 - 284 pages
...Thus, if we have the proportion 3 : 6 : : 6 : 12, t we shall also have = 62 = 3xl2=36. QUEST. — 155. If the product of two quantities is equal to the product of two other quantities, may the four be placed in a proportion 1 How ? — 156. If three quantities are proportional, what...