A municipal bond service has three rating categories(A, B, andC). Suppose that in the pastyear, of the municipal bonds issued thoughout acountry,50 % were rated A, 30%were rated B, and 20 % were rated C. Of the municipal bonds ratedA,40 % were issued bycities,50 % bysuburbs, and 10 % by rural areas. Of the municipal bonds rated B, 70 % were issued bycities,20 % by suburbs, and 10 % by rural areas. Of the municipal bonds rated C,80 % were issued bycities,5 % by suburbs, and 15 % by rural areas.
1. If a new municipal bond is to be issued by a city, what is the probability that it will receive an A rating?
2. What proportion of municipal bonds are issued by cities?
3. What proportion of municipal bonds are issued by suburbs?