If the purchasing power of money decreases by 5% per year due to inflation, after 4 years, the purchasing power of the same amount of money will have decreased by a total of 4 * 5% = 20%. This means that the same amount of money will be able to buy 20% less than it could before.
To find out how many movie tickets the same amount of money could buy in 4 years, we can calculate the purchasing power of the money as follows:
Current purchasing power: 100% - 20% = 80%
This means that the same amount of money will have 80% of its current purchasing power in 4 years. To find out how many movie tickets this corresponds to, we can divide the current number of movie tickets that the money can buy by the purchasing power:
Movie tickets in 4 years = 86 movie tickets / 0.8 = 107.5 movie tickets
Rounded to the nearest whole number, this corresponds to 108 movie tickets. Therefore, the same amount of money that can currently buy 86 movie tickets will be able to buy 108 movie tickets in 4 years.