Mathematic's Quiz (September)

Question:
A farmer has at least 12 cattles that consist of cows and goats. The farmer ever told to sell all of his cattles at the price of Rp 3.000.000,00. The price of a cow is at least Rp 300.000,00 and the price of a goat is at least Rp 200.000,00. One day, the farmer sells of his cattles, where the profit of each cow is Rp 50.000,00 and the profit of each goat is Rp 40.000,00.
a. If the profit is minimum, find the number of cows and goats!
b. Find the minimum profit!

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3. Mathematic's Quiz is closed on September 30, 2008.
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