The task is to generate the correct answer for a given math problem.

Example Input: Problem: company c sells a line of 20 products with an average retail price of $ 1,200 . if none of these products sells for less than $ 400 , and exactly 10 of the products sell for less than $ 1,000 , what is the greatest possible selling price of the most expensive product ?
Example Output: 11000

Example Input: Problem: the average of first 22 natural numbers is ?
Example Output: 11.5

Example Input: Problem: 30 % of employees are women with fair hair . 40 % of fair - haired employees are women . what percent of employees have fair hair ?
Example Output:
7