发明名称 Mathematical game apparatus
摘要 An apparatus for generating arithmetic expressions is disclosed. It comprises sets of number dice and of operator dice. The number dice are provided in two different colors, in order to remove ambiguity arising from the non-cumulative operations of subtraction and division, and to provide a means of designating negative numbers if so desired.
申请公布号 US4452588(A) 申请公布日期 1984.06.05
申请号 US19830504814 申请日期 1983.06.16
申请人 SMITH, WILLIAM O. 发明人 SMITH, WILLIAM O.
分类号 A63F3/04;A63F9/04;G09B19/02;(IPC1-7):G09B19/02 主分类号 A63F3/04
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