The number combinations, their relative difficulty and the frequency of their appearance in text-books; a brief summary of study no. 1
By: by Frank L. Clapp.
Series: The University of Wisconsin. Bureau of Educational Research. Bulletin; no. 1. March, 1924
Published: 1924
Place of publication: Madison, Wis
Language: eng
Number of pages: 19
Subjects: Arithmetic -- Study and teaching; Educational psychology