The owner of an off-street parking located in an urban town has observed that 20% of those wishing to park are turned back every day during the open hours of 8

The owner of an off-street parking located in an urban town has observed that 20% of those wishing to park are turned back every day during the open hours of 8.00am to 6.00pm because of lack of parking spaces. An analysis of data collected at the car park indicates that 60% of those who park are commuters, with an average parking duration of 9 hours, and the remaining are shoppers whose average parking duration is 2 hours. If 20% of those who cannot park are commuters and the rest are shoppers, and a total of 200 vehicles currently park daily. Determine the number of additional spaces required to meet the excess demand. Assume parking efficiency is 0.9.