. Scientific American Volume 79 Number 17 (October 1898). Fig. 10.—Multiplying 6x6. Fig. 11.—Multiplying 14 X 13. Fig. 12.—Multiplying 16 X 17. RAPID METHOD OF MULTIPLICATION WITH THE FINGERS. and has invented a system which, for ingenuity andsimplicity, leaves little to be desired. Procopovitchhad often noticed that children used their fingers inmathematical computations which were at all difficult tothem, and hence devised a method of manual multipli-cation that has been successfully used in many Euro-pean schools. Procopovitchs system neglects all pro-ducts involving numbers less than 6, be
. Scientific American Volume 79 Number 17 (October 1898). Fig. 10.—Multiplying 6x6. Fig. 11.—Multiplying 14 X 13. Fig. 12.—Multiplying 16 X 17. RAPID METHOD OF MULTIPLICATION WITH THE FINGERS. and has invented a system which, for ingenuity andsimplicity, leaves little to be desired. Procopovitchhad often noticed that children used their fingers inmathematical computations which were at all difficult tothem, and hence devised a method of manual multipli-cation that has been successfully used in many Euro-pean schools. Procopovitchs system neglects all pro-ducts involving numbers less than 6, because, as wehave already observed, these products are readilylearned by most children. The Polish mathematician first numbers the fingersof each hand. The two thumbs each represent 6, theindex-fingers 7, the middle fingers 8, the ring-fingers 9,and the little fingers 10. In order to multiply any twoof these numbers, the fingers representing the multi-plier and the multiplicand are placed end to end. Be-ginning with the fingers which have been thus
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