A 5-day pass to all art galleries for one person costs $180. The management gives a concession to a group of 45 tourists. For every 3 tourists who purchase the 5-day pass, the 4th tourist gets free access to the art galleries. How much does each tourist pay in this arrangement if they share the total cost equally?
For every 3 tourists, 4th tourist gets free access.

Number of tourists in eact set
= 3 + 1
= 4

Number of sets of 4 tourists
= 45 ÷ 4
= 11 r 1 

There are 11 sets of 4 tourists in 45 tourists, so 11 tourists will get free access.

Number of tickets to be paid for
= 45 - 11
= 34

Total cost of tickets
= 34 x 180
= $6120

Cost for each tourist
= 6120 ÷ 45
= $136
 
Answer(s): $136