Population Number of Cities
10,000-under 25,000 1476
25,000-under 50,000 664
50,000-under 100,000 407
100,000 under 250,000 182
250,000-under 500,000 37
500,000-under 1,000,000 23
1,000,000 or more 9

The breakdown of U.S. cities having a population of at least 10,000 persons has been reported as follows.

a. How many cities have a population of at least 25,000 but less than 500,000?
b. How many cities have a population less than 250,000?
c. How many cities have a population of at least 100,000 but less than 1,000,000? What percentage of cities are in this group?
d. What is the class mark for the 100,000-under 250,000 class?
e. Convert the table to a relative frequency distribution.