An airline charges the following baggage fees: $30 for the first bag and $35 for the second. Suppose 51% of passengers have no checked luggage, 27% have only one piece of checked luggage and 22% have two pieces. We suppose a negligible portion of people check more than two bags.

Answer 1

sounds reasonable.
So, what? Something tells me you want something involving
0.51(0) + 0.27(30) + 0.22(35)
which would be the cost for all the expected checked bags