Excel Solver-maximize annual passenger-carrying capability

An airline owns an aging fleet of jet airplanes. It is considering a major purchase of up to 17 new model 7a7 and 7b7 jets. The decision must take into account numerous cost and capability factors, including the following: (1) The airline can finance up to $400 million in purchases; (2) each 7a7 jet will cost $35 million and each 7b7 jet will cost $22 million; (3) at least one third of the planes purchased should be the longer range 7a7; (4) the annual maintenance budget is to be no more than $8 million; (5)the annual maintenance cost per 7a7 is estimated to be $800,000, and it is $500,000 for each 7b7 purchased; and (6) each 7a7 can carry 125,000 passengers per year, and each 7b7 can fly 81,000 passengers annually. Formulate this as an IP problem to maximize the annual passenger-carrying capability. Solve using Excel.