At Café Alpha, a coffee costs $3.00 and a donut costs $2.00. At Café Beta, a coffee costs $2.50 and a donut costs $3.00. A customer purchases a certain number of coffees and donuts, which cost $16.00 at Café Alpha or $20.00 at Café Beta. What is the total number of coffees and donuts purchased?
6
7
8
9
