math
posted by kwame on .
1. A teacher has 10 boys and 12 girls in her grade school class. In how many ways can she select 8 of the children to be in a play if she must select 5 boys and 3 girls.
2. The manager of the various displays in the Acme Fine Clothing Emporium has a window which will hold 4 dummies. He has 8 dummies, each showing a different style outfit, from which to choose. How many different displays can he arrange in his display window? (If the order in which the dummies appear changes, it is regarded by the manager as ‘a different display.)
3. If you buy a $300,000 house, paying 5% down, and take out a 25 year, fixed rate of 6.5%, loan, then your monthly payments for principal and interest will be
4. Three coins are tossed. Find the probability that all the coins land heads up
5. Two dice are rolled. Find the probability of getting a sum greater than 10.
6. A person rolls two dice. What are the odds in favor of throwing at least an eight?
7. A lottery has one $2000 prize, two $1000 prizes, and ten $500 prizes. Thirtysix hundred tickets are sold at $4 each. Find the expected value if a person buys two tickets.
8. A card is drawn from a standard 52 card deck. What is the probability that it is either a red ‘ace or a black king?
9. A card is drawn from a standard 52 card deck. What is the probability that it is either a red’ ace or a black king?
10 How many three symbol codes using the digits 2 through 9 are possible if repetitions are allowed? (243 is an example of a three symbol code.)
11. An urn contains 5 red marbles, 4 blue marbles, and 3 green marbles. A marble is selected at random and then, without replacing the first marble, a second marble is selected at random. What is the probability of selecting a green marble and then a red marble?
12. In a classroom, the students are 20 boys and 28 girls. If one student is selected at random, find the probability that the student is a boy.

If you include only a couple of problems in each post, along with your attempts of answers, someone may be able to help you.
If you don't do this, I will assume that you don't want help, just answers.