Aeroplane is an important invention for three reasons. It shortens travel time, is more comfortable and facilitates the transport of heavy cargo.
An aeroplane can carry a maximum of 200 passengers.
A profit of ₹400 is made on each executive class ticket and a profit of ₹300 is made on each economy class ticket. The airline reserves at least 20 seats for executive class. However at least 4 times as many passenger prefer to travel by economy class than by executive class.

Based on above information answer the following questions.
i. If x tickets of executive class and y tickets of economy class be sold, then write the constraint.
ii. Write the correct pair of constraints.
iii. If profit earned by airlines is represented by Z, then write the constraint.
iv. Airlines are interested to maximise the profit. For this what are the value of x and y i.e.r number of executive class ticket and economy class ticket to be sold?
v. What is the maximum profit earned by airlines?