The task is to generate the correct answer for a given math problem.
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Question: Problem: a rectangle having length 105 cm and width 40 cm . if the length of the rectangle is increased by twenty five percent then how much percent the breadth should be decreased so as to maintain the same area .

Answer: 19.23 %


Question: Problem: a car salesman earns a base salary of $ 1000 per month plus a commission of $ 200 for each car he sells . if the car salesman earned $ 2000 in march , how many cars does he need to sell in april in order to double his march earnings ?

Answer: 15


Question: Problem: in a group of ducks and cows , the total number of legs are 40 more than twice the number of heads . find the total number of cows .

Answer:
2