math

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(d) 4P2 (e) 5C4 (f) 9P6

2. If there are 5 ways to travel from town A to town B, and 6 ways to travel from town B to town C, how many different ways are there to travel from town A to town C?

3. If an ice cream parlor has 15 different flavors of ice cream, 10 different toppings, and 4 different styles of cones, how many different varieties of ice cream cones are available to the customer?

4. The Postal Service is encouraging the use of 9-digit zip codes in most areas. How many zip codes are possible

(a) if there are no restrictions on the digits used?

(b) if only odd numbers can be used?

(c) if the first number cannot be zero and the second number must be 1?

5. How many different 6-letter radio station call letters can be made

(a) if the first letter must be K, and no letter may be repeated?

(b) if the first letter must be K, the fourth letter must be B, and no letter may be repeated?

(c) if repeats are allowed (but the first letter is K or and the fourth letter is B)?

6. How many 7-member committees can be formed from a class consisting of 21 students? What if two of the students must be included on the committee?

7. In a game of musical chairs, 10 children will sit in 6 chairs arranged in a row. Four children will be left out. In how many ways can the 10 children find seats?

8. A mailman has special delivery mail for 9 customers.

(a) In how many ways can he arrange his schedule to deliver to all 9?

(b) In how many ways can he schedule deliveries if he can deliver to only 5 of the 9?

9. Six orchids are to be selected from a collection of 14 for a flower show.

(a) In how many ways can this be done?

(b) In how many different ways can the group of 6 be selected if 3 particular orchids must be included?

10. A die is rolled 8 times. Find the probability of rolling

(a) Exactly 3 twos (b) Exactly 4 threes (c) No more than 4 fives

11. A coin is tossed 9 times. Find the probability of rolling

(a) All heads (b) Exactly 4 tails (c) At least 5 heads

12. Sixty-five percent of all students at a certain school ski. If a sample of 35 students at this school is selected, and if their responses are independent, find the probability that exactly

(a) 15 of the 35 students ski (b) All 35 students ski