Charles has 24 marbles. He has 6 more yellow marbles that blue marbles. Which equation represents this situation?
1) n+6n=24 where n is the number of yellow marbles
2)n+(n+6)=24, where n is the number of yellow marbles
3) n+6n=24 where n is the number of blue marbles
4)n+(n+6)=24, where n is the number of blue marbles