In 1790, the first Census of the United States counted 144,000 free citizens in New Hampshire, which meant that the Granite State got four seats in the House of Representatives. But South Carolina, with 140,000 free citizens and 100,000 slaves, got six seats. The population of Massachusetts was greater than the population of Virginia, but Virginia had 300,000 slaves and so got five more seats. If not for the three-fifths rule, the representatives of free states would have outnumbers representatives of slave states by 57 to 33.
Jill Lepore, These Truths, 125.