Why did 12 states send delegates to philadelphia in 1787

From May 25 to September 17, 1787, 55 delegates from 12 statesconvened in Philadelphia for the Constitutional Convention. Rhode Island was the only state that refused to send representatives to the convention, which assumed as its primary task the revision or replacement of the Articles of Confederation.

There would be 12 chromosomes found in that organism's body cells. i know this because the # of chromosomes is half the number of body cells. 

He educates the people on the true conditions on how the poor people are actually living. he brings up death tolls, gruesome images, and the true state of the apartment buildings