Problem:
There are cities in the County of Newton. Their populations are shown in the bar chart below. The average population of all the cities is indicated by the horizontal dashed line. Which of the following is closest to the total population of all cities?
Answer Choices:
A.
B.
C.
D.
E.
Solution:
Looking at the horizontal dashed line, the average population is around . Since there are cities, and the average population is given by:
we know:
Multiplying both sides by yields:
Thus, the correct answer is .
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions