Question 1106954
Average is total/n
89*3=267 total points
x first exam, x+10 second, and x+11 is third
3x+21 is total=267
3x=246
x=82 on first exam
92 on secod
93 on third
82 is 7 below the average, 92 is 3 above, 93 is 4 above, so checks.