What issue did the great compromise and the three-fifths compromise resolve?

It resolved the problems of how the states should be respresented

This resolved the issue of votes in the congress during the congressional convention.
The Great Compromise was a solution that developed the seperate entities of the House of Representatives, which had a proportional representation based on population of the state, and the Senate, which had a flat rate of two representatives per state.
The Three-Fifths Compromise, as awful as it may be, achieved the same thing. There was a controversy about whether or not slaves counted when figuring out the amount of representatives a state got in the House. It was decided that a slave was worth 3/5 of a person, and that could be used to calculate House representatives for a state. 

Let me know if you need more detail. Hope this helps

Ithink it's a, but i might be wrong