Time to half spent photocopying
For each class: 27 minutes (approx)
For number of classes they took photocopies: 27 * 27 = 729 minutes
This equates to 12 hours and 9 minutes.
Number photocopied sheets per semester
For each class: 96 * 3 = 288 sheets
for approx number of classes: 288 * 27 = 7776
What equivalent to 93.3% of a tree :-(
