What was the law that stated that every 5 slaves would count as 3 people for taxation and representation purposes?

The Three-Fifths Compromise

Explanation:

The Three-Fifths Compromise (devised at the Constitutional Convention in 1787) stated that every three out of five slaves would be counted for taxation and representation purposes, and was the beginning of many compromises between pro and anti-slavery advocates leading up to the Civil War.

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