Last question of the Level 3 test

Now that everyone should have finished their Level 3 test, I am going to post the solutions to the last question.

Question: A number of students are going on an excursion that is of a set price. 2 students decided that they would not like to participate and the rest of the students had to pay an extra 36cents. Before the excursion 1 of the 2 students decided to join and the other students were refunded 20cents. How many students are going on the excursion.