Why was it hard for the framers to agree on how many representative a state should be able to send to congress?

It was hard for the framers to agree on how many representatives each state should be able to send to congress because the smaller states were wanting the same amount of representatives from each state (not based on its population, and the larger states wanted to have it based on their population (so it would give them a better chance of winning a vote). The larger states wanted the Virginia Plan, based on population. The smaller states wanted the New Jersey Plan, which meant every state got equal representation aka 1 vote. They came to a compromise with the Great Compromise.