Books Books To express that the ratio of A to B is equal to the ratio of C to D, we write the quantities thus : A : B : : C : D; and read, A is to B as C to D. Manual of Geometry and Conic Sections: With Applications to Trigonometry and ... - Page 70
by William Guy Peck - 1876 - 366 pages ## New Plane Geometry

Webster Wells - Geometry, Plane - 1908 - 208 pages
...POLYGONS DEFINITIONS 210. A Proportion is a statement that two ratios are equal. 211. The statement that the ratio of a to b is equal to the ratio of c to d is written a_£ b~d 212. In the proportion - = -, we call a the first term, b the 0 Cd second term,... ## The First Steps in Algebra

George Albert Wentworth - Algebra - 1908 - 246 pages
...formed by two equal ratios a : b and с ; d may Ъе written in three ways : (1) a : b = с : d (read, the ratio of a to b is equal to the ratio of о to d). (2) a : b : : с : d (read, a is to b as с is to d), a and d are the extremes, b and с... ## Standard Algebra

William James Milne - Algebra - 1908 - 476 pages
...lines that form the sign of equality. The proportion a : b = с : d, or a : b : : с : d, is read, ' the ratio of a to b is equal to the ratio of с to d,' or 'a is to b as с is to d.' 473. In a proportion, the first and fourth terms are called... ## School Algebra

James William Nicholson - Algebra - 1909 - 332 pages
...equation whose members are ratios. Thus, о : 6 = с : d, or - = li a is a proportion, which is read, the ratio of a to b is equal to the ratio of с to d. The same proportion is sometimes written a:b::c:>l, which is read, a is to 6 as с is to d.... ## Appleton's New Practical Cyclopedia: A New Work of Reference Based ..., Volume 5

...proportion when the ratio of the first to the second is equal to the ratio of the third to the fourth. A proportion may be written in either of two ways;...d, the equality may be indicated by either of the following expressions: ld — = — , or a : b : : c : d. Either of them may be read a is to b as c... ## Elements of Plane Geometry

William Herschel Bruce, Claude Carr Cody (Jr.) - Geometry, Modern - 1910 - 286 pages
...: ac — = — ; a:b::c:d; a : 0 = c : a. 6 d This proportion is read "a is to 6 as c is to d"; or "the ratio of a to b is equal to the ratio of c to d." 312. The four quantities, a, 6, c, and d, are called the terms of the proportion. 313. The first and... ## First Year Algebra

William James Milne - Algebra - 1911 - 380 pages
...extremities of the lines that form the sign of equality. The proportion a:b = c:d, or a:b::c:d, is read, ' the ratio of a to b is equal to the ratio of с to d,' or ' о is to b as с is to d.' 389. In a proportion, the first and fourth terms are called... ## First Year Algebra

Webster Wells, Walter Wilson Hart - Algebra - 1912 - 344 pages
...which are as 5 : 3 : 2. 212. A Proportion is a statement that two ratios are equal. The statement that the ratio of a to b is equal to the r,atio of с to d is written either а с , , — = -, or a : о = с : a. о а This proportion is read " a... ## Second Course in Algebra

Webster Wells, Walter Wilson Hart - Algebra - 1913 - 362 pages
...which are as о : 3 : 2. 184. A Proportion is a statement that two ratios are equal. The statement that the ratio of a to b is equal to the ratio of с to d is written either а с , ., — = -, or а: b = c: a. bd This proportion is read " a is to... 