Arithmetic instructional apparatus

Description

FIG. 1 is a plan view of an arithmetic instructional device showing my new design;

FIG. 2 is a side view of the arithmetic instructional device of FIG. 1; and,

FIG. 3 is a bottom view of the arithmetic instructional device of FIG. 1.

The FIG. 1 view has been shaded to indicate color.

Referenced Cited
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D354314 January 10, 1995 Steininger
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Patent History
Patent number: D394878
Type: Grant
Filed: Apr 21, 1997
Date of Patent: Jun 2, 1998
Inventor: Irma Maritza Perez (Bloomfield, NJ)
Primary Examiner: Martie Thompson
Application Number: 0/69,485
Classifications
Current U.S. Class: Teaching Material (D19/59); Movable Indicator Or Changeable Exhibitor (D19/64)
International Classification: 1907;