My statistics professor gave us an assignment using the Census website. I had to look at the population of my zipcode from 2010; which was 39,150. She wants us to find the median age, which is already given to us; it is 44.9 years old. She also wants us to find the mean age and we must show all our calculations on how we found the mean age. I understand what mean is but i do not understand how to find it from this information:

39,150
1,962
1,933
2,030
1,975
1,950
2,143
2,434
2,484
2,746
2,905
2,919
2,764
2,618
2,163
1,855
1,476
1,369
1,424