The American accountant; or, Schoolmasters' new assistant. [electronic resource] : Comprised in four books. Book I. Containing arithmetic of whole numbers,--divers denominations, and the common rules, to the end of the double rule of three. Book II. Fractions, vulgar and decimal. Book III. Mercantile arithmetic; or all the rules necessary for forming a complete accountant; methodically arranged and largely exemplified. Book IV. Extractions, progressions, &c. being the higher rules of arithmetic. And including all the questions in the Philadelphian edition of Gough, with many others. The rules are either new, or those of that treatise so far compendized as to be both brief and perfectly applicable. The whole adapted to the commerce of the United States; and comprehending every thing necessary to a complete practical knowledge of the science of arithmetic. By Benjamin Workman, A.M.