Visual teaching aid

Education and demonstration – Mathematics

Reexamination Certificate

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Reexamination Certificate

active

07014468

ABSTRACT:
An aid for teach addition and subtraction comprises a single counting member representing a single digit, and consecutive sets of counting members progressing numerically from two members to ten members. The members of each set are interconnected for pivotal displacement relative to one another, and each counting member is provided with shape and color indicia.

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