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

Example Input: Problem: john left home and drove at the rate of 45 mph for 2 hours . he stopped for lunch then drove for another 3 hours at the rate of 45 mph to reach his destination . how many miles did john drive ?
Example Output: 225 miles .

Example Input: Problem: a person was asked to subtract 25 % of a number from the original but he subtracted 25 from the number . his answer was 25 more than correct one . what was the original number ?
Example Output: 200

Example Input: Problem: a ferry can transport 50 tons of vehicles . automobiles range in weight from 1,800 to 3,200 pounds . what is the greatest number of automobiles that can be loaded onto the ferry ?
Example Output:
55