When 43 books were checked out on Wednesday, Suzy remained with 98 - 43 = <<98-43=55>>55 books
After 23 books were returned on Thursday, she ended with 55 + 23 = <<55+23=78>>78 books
However, 5 books were checked out on the same day meaning that 78 - 5 = <<73=73>>73 books were left.
After 7 books were returned on Friday, Suzy had 73 + 7 = <<73+7=80>>80 books
#### 80