1. Pre-Calculus Section 8.6A Counting Principles

2. 1. Eight pieces of paper are numbered 1 to 8 and placed in a box. One piece of paper is drawn from the box, its number is written down, and the piece of paper is returned to the box. Then, a second piece of paper is drawn from the box and its number is written down. Finally, the two numbers are added together. In how many different ways can a sum of 12 occur?

3. 2. Eight pieces of paper are number from 1 to 8 and placed in a box. Two pieces of paper are drawn from the box at the same time, and the numbers on the paper are written down and totaled. In how many ways can a sum of 12 occur?

4. Fundamental Counting Principal

5. 3. How many different pairs of letters from the English alphabet are possible?

6. 4. Telephone numbers in the United States currently have 10 digits. The first three are the area code and the next seven are the local telephone number. How many different telephone numbers are possible within each area code? (Note that at this time a local telephone number cannot begin with a 0 or 1)

7. 5. Determine the number of ways in which a computer can randomly generate an integer that is divisible by 4 from the numbers 1 through 12.

8. 6. A customer can choose from one of four amplifiers, one of six compact disc players, and one of five speaker models for an entertainment system. Determine the number of possible system configurations.

9. 7. In 1963 the US Postal Service launched the Zoning Improvement Plan (ZIP) Code to streamline the mail-delivery system. A ZIP code consists of a five-digit sequence of numbers. a) find the number of ZIP codes consisting of five digits.

10. 7. In 1963 the US Postal Service launched the Zoning Improvement Plan (ZIP) Code to streamline the mail-delivery system. A ZIP code consists of a five-digit sequence of numbers. b) find the number of ZIP codes consisting of five digits, if the first digit is a 1 or 2.