11 1 Introduction to Probability Warm Up Problem

11 -1 Introduction to Probability Warm Up Problem of the Day Lesson Presentation Course 1

11 -1 Introduction to Probability Warm Up Write each fraction as a decimal and as a percent. 3 __ 1. 4 0. 75; 75% 1 __ 2. 2 0. 50; 50% __ 2 __ 3. 9 0. 2; 22. 2% 3 __ 4. 8 0. 375; 37. 5% Course 1

11 -1 Introduction to Probability Problem of the Day What fraction of the numbers from 0 to 99 are divisible by 3? . 34 or __ 17 ___ 100 50 Course 1

11 -1 Introduction to Probability Learn to estimate the likelihood of an event and to write and compare probabilities. Course 1

11 -1 Introduction Insert Lesson Here to. Title Probability Vocabulary probability Course 1

11 -1 Introduction to Probability is the measure of how likely an event is to occur. Course 1

11 -1 Introduction to Probability Probabilities are written as fractions or decimals from 0 to 1 or as percents from 0% to 100%. The higher an event’s probability, the more likely that event is to happen. • Events with a probability of 0, or 0%, never happen. • Events with a probability of 1, or 100%, always happen. • Events with a probability of 0. 5, or 50%, have the same chance of happening as of not happening. Course 1

11 -1 Introduction to Probability Impossible 0 0% Unlikely As likely as not 0. 5 1 __ 2 50% Course 1 Likely Certain 1 100%

11 -1 Introduction Insert Lesson Here to. Title Probability Additional Example 1 A & 1 B: Estimating the Likelihood of an Event Write impossible, unlikely, as likely as not, likely, or certain to describe each event. A. You will roll an even number on a standard number cube. as likely as not B. The month of February has 28 days. certain Helpful Hint A standard number cube is numbered from 1 to 6. Course 1

11 -1 Introduction Insert Lesson Here to. Title Probability Additional Example 1 C & 1 D: Estimating the Likelihood of an Event Write impossible, unlikely, as likely as not, likely, or certain to describe each event. C. This spinner lands on blue. unlikely D. This spinner lands on an odd number. impossible Course 1

11 -1 Introduction Insert Lesson Here to. Title Probability Try This: Example 1 A & 1 B Write impossible, unlikely, as likely as not, likely, or certain to describe each event. A. You guess a number between 1 and 1000. unlikely B. You will roll an odd number on a standard number cube. as likely as not Helpful Hint A standard number cube is numbered from 1 to 6. Course 1

11 -1 Introduction Insert Lesson Here to. Title Probability Try This: Example 1 C & 1 D Write impossible, unlikely, as likely as not, likely, or certain to describe each event. C. This spinner lands on green. unlikely D. This spinner lands on an even number. certain Course 1

11 -1 Introduction Insert Lesson Here to. Title Probability Additional Example 2 A & 2 B: Writing Probabilities A. The weather report gives a 75% chance of snow. Write this probability as a decimal and as a fraction. 75% = 0. 75 Write as a decimal. 75 3 Write as a fraction in 75% = ___ = __ simplest form. 100 4 B. The chance of being chosen is 0. 8. Write this probability as a fraction and as a percent. 8 4 __ __ 0. 8 = = 10 5 0. 8 = 80% Course 1 Write as a fraction in simplest form. Write as a percent.

11 -1 Introduction Insert Lesson Here to. Title Probability Additional Example 2 C: Writing Probabilities 7 __ C. There is a chance of getting a ring. Write 50 this probability as a decimal and as a percent. 7 __ = 7 ÷ 50 = 0. 14 50 Write as a decimal. 7 7 • 2 14 __ = ___ = 14% 50 50 • 2 100 Write as a percent. Helpful Hint In Example 2 C, after you find the decimal form 7 , you can use it to find the percent. of __ 50 0. 14 = 14%. Course 1

11 -1 Introduction Insert Lesson Here to. Title Probability Try This: Example 2 A & 2 B A. The weather report gives a 25% chance of snow. Write this probability as a decimal and as a fraction. 25% = 0. 25 Write as a decimal. 25 1 Write as a fraction in 25% = ___ = __ simplest form. 100 4 B. The chance of being chosen is 0. 6. Write this probability as a fraction and as a percent. 6 3 __ __ 0. 6 = = 10 5 0. 6 = 60% Course 1 Write as a fraction in simplest form. Write as a percent.

11 -1 Introduction Insert Lesson Here to. Title Probability Try This: Example 2 C 4 __ C. There is a chance of getting a ring. Write 25 this probability as a decimal and as a percent. 4 __ = 4 ÷ 25 = 0. 16 25 Write as a decimal. 4 4 • 4 16 __ = ___ = 16% 25 25 • 4 100 Write as a percent. Course 1

11 -1 Introduction Insert Lesson Here to. Title Probability Additional Example 3 A: Comparing Probabilities A. On a standard number cube, there is a 50% 1 __ chance of rolling a multiple of 2 and a 33 % 3 chance of rolling a multiple of 3. Is it more likely to roll a multiple of 2 or a multiple of 3? 1 Compare: 33 __% < 50% 3 It is more likely to roll a multiple of 2. Course 1

11 -1 Introduction Insert Lesson Here to. Title Probability Additional Example 3 B: Comparing Probabilities B. When you spin a certain spinner, there is a 15% chance that it will land on yellow, a 15% chance it will land on green, and a 70% chance that it will land on purple. Is it more likely to land on purple or on green? Compare: 70% > 15% It is more likely to land on purple than on green. Course 1

11 -1 Introduction Insert Lesson Here to. Title Probability Try This: Example 3 A A. When you spin a certain spinner, there is a 25% chance that it will land on purple, a 35% chance it will land on green, and a 40% chance that it will land on red. Is it more likely to land on red or on green? Compare: 40% > 35% It is more likely to land on red than on green. Course 1

11 -1 Introduction Insert Lesson Here to. Title Probability Try This: Example 3 B B. When you spin a certain spinner, there is a 1 9% chance that it will land on yellow, a 35 __ % 3 2 % chance it will land on brown, and a 55 __ 3 chance that it will land on blue. Is it more likely to land on brown or on yellow? 1 __ Compare: 9% < 35 % 3 It is more likely to land on brown than on yellow. Course 1

11 -1 Introduction Insert Lesson to. Title Probability Here Lesson Quiz Write impossible, unlikely, equally likely, or certain to describe each event. 1. The sun will rise tomorrow. certain 2. You will roll 13 when rolling two dice. impossible 3. There is a 0. 125 chance of picking the winning ticket. Write this probability as a fraction and as a 1 , 12. 5% percent. __ 8 4. At Hamburger Hut, there is a 20% chance of getting a plastic dinosaur cup and a 35% chance of getting a plastic rabbit cup. It is less likely that you will receive a rabbit cup or dinosaur cup? dinosaur cup Course 1