- An Aeroplane can carry a maximum of 200 passengers. A profit of Rs. 400 is made on each first class ticket and a profit of Rs. 300 is made on each economy class ticket. - The airline reserves at least 20 seats for first class. - However, at least 4 times as many passengers prefer to travel by economy class than by the first class. - How many tickets of each class must be sold in order to maximize profit for the airline? Formulate the problem as an mode