The decimal point is 1 digit(s) to the right of the |

  4 | 8
  5 | 
  5 | 9
  6 | 00
  6 | 8
  7 | 00012
  7 | 5677888999
  8 | 1334
  8 | 55799
  9 | 3
  9 | 7

The first, second, and third quartiles of the exam were 70.5, 78, and 83.5, respectively.