Problema Solution

The average price of a movie ticket in a certain city was $10 in 2010, and it increases at 5% per year.

A: write the equation of the exponential function that models the average price of a movie ticket t years after 2010.

B: use the model to predict the average price of a movie ticket in 2015

Answer provided by our tutors

A: write the equation of the exponential function that models the average price of a movie ticket t years after 2010.


after 1 year the ticket will be: 10 + 0.05*10 =10(1 + 0.05)


after 2 years the ticket will be: 10(1 + 0.05) + 10(1 + 0.05)*0.05 = 10(1 + 0.05)^2


after 3 years the ticket will be: 10(1 + 0.05)^3


after x years the ticket will be


f(x) = 10(1 + 0.05)^x, where x is the number of years after 2010



B: use the model to predict the average price of a movie ticket in 2015


for the year 2015, x = 2015 - 2010 = 5


f(5) = 10(1 + 0.05)^5


f(5) = $12.73


the average price of a movie ticket in 2015 will be $12.73.