Okay so you gotta do Rial's score, which is 100,034 minus how much less Lexi's score is, 9,348 and that equals Lexi's score which is 90,686. So your first equation is
100,034 - 9,348 = 90,686
then you have to add 9,749 to Lexi's score of 90,686.
So Susie's score is 100,435
Hope this helps!