At Max's party 3/12 of the guests are 10 years old and 7/12 of the guests are II years old what fraction of the guests are 10 or 11 years old?

Juanita wade's new car has an msrp of $28,902.11 including title and processing fees. the premier package which includes surround sound and dvd player costs three times the amount of the in-style package which includes leather seats and select wheels. the total cost of her new car was $34,290.08 which included the 6.5% sales tax. find the cost of the premier package to the nearest cent.