1. Example 2 Writing a Probability as a Percent Prizes A radio station randomly selects 1 of 5 finalists for a prize. You are one of the finalists. What is the probability that you will win? Write your answer as a percent. SOLUTION There are 5 possible outcomes, and 1 outcome is favorable. Write fraction as a percent. = 20% Write probability as a fraction. = P (you win) 5 1 ANSWER The probability that you will win is 20%.

2. Example 3 Finding a Percent of a Number Tortoises A desert tortoise can go a year or more without drinking water. When it does drink, its body weight can increase by 40%. Suppose a desert tortoise weighs 15 pounds after a long period without water. How many pounds can the tortoise gain when it drinks ? Write percent as a fraction. = 40% of 15 5 2 15 = SOLUTION To find 40% of 15 pounds, use the fact that 40% Then multiply. 5 2.

3. Multiply. = 5 30 Example 3 Finding a Percent of a Number Simplify. = 6 ANSWER The desert tortoise can gain 6 pounds when it drinks.

4. Checkpoint ANSWER 10% 5. In Example 2, suppose that there are 10 finalists. What is the probability that you will win ? Write your answer as a percent.

5. Checkpoint 70% of 70 7. ANSWER 49 50% of 14 8. ANSWER 7 75% of 80 9. ANSWER 60 25% of 36 6. ANSWER 9 Find the percent of the number.