In a marathon,90% of runners managed to complete it and 30% where men. if 270 men completed it, how many total runners began the marathon

Use the elimination method to find the solution to the system of equations. 2x - 3y = -9 -x + 3y = 6

Can someone me and plz do the problem

Sue's average score for three bowling games was 162. in the second game, sue scored 10 less than in the first game. in the third game, she scored 13 less than in the second game. what was her score in the first game?