Arithmetick made easie, for the use and benefit of trades-men. [electronic resource] : Wherein the nature and use of fractions, both vulgar and decimal, are taught by a new and exact method. Also the mensuration of solids and superficies. The eighteenth edition. By J. Ayres, late writing-master in St. Paul's Church-Yard, London. To which is added, a short and easie method; after which shop-keepers may state, post, and balance their books of accompts. By Charles Snell, writing-master, and accomptant, in Foster-Lane, London. The whole perused, and many errours corrected by E. Hatton, gent.