Books Books In any proportion, the product of the means is equal to the product of the extremes. Elements of Plane Geometry: For the Use of Schools - Page 53
by Nicholas Tillinghast - 1844 - 96 pages ## The Packard Commercial Arithmetic

Silas Sadler Packard, Byron Horton - Business mathematics - 1882 - 324 pages
...a proportion are called the extremes ; and the second and third, the means. 385. PRINCIPLES. — I. The product of the means is equal to the product of the extremes. 3. A missing extreme may be found by dividing the product of the means by the given extreme. 386. To... ## The Packard Commercial Arithmetic

Silas Sadler Packard, Byron Horton - Business mathematics - 1882 - 224 pages
...proportion are called the extremes ; and the second and third, the means. 385. PRINCIPLES. — 1. Tlie product of the means is equal to the product of the extremes. 2. A missing mean may be found by dividing the product of the extremes by the given mean. 3. A missing... ## Geometry - Plane, Solid and Analytic Problem Solver

Research & Education Association Editors, Ernest Woodward - Mathematics - 2012 - 1080 pages
...congruent angles. 10. AA = AA 11. Corresponding sides of similar triangles are in proportion. 12. In a proportion, the product of the means is equal to the product of the extremes. • PROBLEM 531 Using Ptolemy's Theorem show that if a anS b, with a ^ b, are chords of two arcs of... ## A Brief Course in Arithmetic

Ann Faber, Gale Edgerton, Paul Karanevich - Mathematics - 1985 - 254 pages
...proportion amounts to multiplying the "means" (inner numbers) and the "extremes" (outer numbers). If the product of the means is equal to the product of the extremes, the ratios are equal. 2X2 = 4 1:2 2:4 1 X4 = 4 4 = 4, so that 1 :2 = 2:4 is a proportion. I Example... ## Geometry I Essentials

The Editors of REA - Mathematics - 2013 - 112 pages
...c are called the means of the proportion. The single term d is called the fourth proportional. In a proportion, the product of the means is equal to the product of the extremes. Theorem 2 A proportion may be written by inversion. (If alb = eld, then bla = die.) Theorem 3 •i... ## Basic Math Concepts: For Water and Wastewater Plant Operators

Joanne K. Price - Technology & Engineering - 1991 - 378 pages
...proportion. The inside terms (2nd and 3rd) are called the means of a proportion. For all proportions, the product of the means is equal to the product of the extremes. In other words, when the two inside terms are multiplied, the answer will be the same as when the two... ## Merriam-Webster's Guide to Everyday Math: A Home and Business Reference

Brian Burrell - Mathematics - 1998 - 386 pages
...or as "/, = '//. The values b and c are referred to as the means; a and d are the extremes. In any proportion, the product of the means is equal to the product of the extremes. (This is also known as cross-multiplication.) THE RULE OF THREE "Do as you would be done by" is thought... ## Schaum's Outline of Basic Mathematics with Applications to Science and ...

Haym Kruglak, John Moore, Ramon Mata-Toledo - Mathematics - 1998 - 508 pages
...of the proportion. The above proportion can be written in fractional form as a/b = c/d. Rule. In any proportion, the product of the means is equal to the product of the extremes. Ratio For instance, 3:4 = 6:8 is a proportion and the product of the means is (4)(6) or 24 and the... ## Apollo's Lyre: Greek Music and Music Theory in Antiquity and the Middle Ages

Thomas J. Mathiesen - Music - 1999 - 832 pages
...proportion" (Kupionepoi; dvaXoyia), in which two middle terms form various ratios with the extremes and the product of the means is equal to the product of the extremes. This proportion is represented by 12:9:8:6, which embraces geometric proportion (12:8::9:6), harmonic... 