Introducing Probability

Probability

Lesson 1: Introduction to Probability

Describing Probability

• Another word for probability is 'chance'

• E.g. What is the chance of flipping a coin and getting a tails?

• E.g. What is the probability that tomorrow is the weekend?

Describing Probability

• We can use any of the words or numbers to represent an event and the chance of an outcome occurring.

• E.g. The chance of flipping a coin and getting a tails is Equally Likely, 0.5 or 50% since there are only two sides on a coin.

• The probability that tomorrow is the weekend is 100%.

Describing Probability Examples

• There is a 1 in 6 chance when rolling a dice and getting a 1.

• It is certain that tomorrow is Saturday.

• It is highly likely that someone is absent from school today.

• It is certain that at least one student in our class will not submit their work today or whose laptop has run out of battery. (prove me wrong)

Describing Probability (with fractions)

Multiple Choice

What does the word 'probability' mean?

• Chance

• Addition

• Subtraction

• Division

Multiple Choice

If something will happen, which word best describes this?

• Impossible

• Unlikely

• Likely

• Certain

Multiple Choice

If something will never happen, which word best describes this?

• Impossible

• Unlikely

• Likely

• Certain

Multiple Choice

If something probably won't happen, which word best describes this?

• Impossible

• Unlikely

• Likely

• Certain

Multiple Choice

If something probably will happen, which word best describes this?

• Impossible

• Unlikely

• Likely

• Certain

Multiple Choice

What is the chance that tomorrow is Monday?

• Impossible

• Unlikely

• Likely

• Certain

Multiple Choice

What is the probability that you will eat food today?

• Impossible

• Unlikely

• Likely

• Certain

Multiple Choice

What is the chance that the Suns lost in the NBA grand finals?

• Impossible

• Unlikely

• Likely

• Certain

Multiple Choice

What is the probability that when you roll a six sided die, you roll a 1?

• $$\frac{1}{6}$$

• $$\frac{2}{6}$$
  

• $$\frac{3}{6}$$

• $$\frac{4}{6}$$
  

Multiple Choice

What is the probability that when you roll a six sided die, you roll a 1 or a 2?

• $$\frac{1}{6}$$

• $$\frac{2}{6}$$
  

• $$\frac{3}{6}$$

• $$\frac{4}{6}$$
  

Multiple Choice

What is the probability that when you roll a six sided die, you roll an even number ?

(2, 4 or 6)

• $$\frac{1}{6}$$

• $$\frac{2}{6}$$
  

• $$\frac{3}{6}$$

• $$\frac{4}{6}$$
  

Multiple Choice

What is the probability that when you roll a six sided die, you roll an odd number ?

(1, 3 or 5)

• $$\frac{1}{6}$$

• $$\frac{2}{6}$$
  

• $$\frac{3}{6}$$

• $$\frac{4}{6}$$
  

Multiple Choice

What is the probability that when I spin this spinner, I land on a 5?

• $$\frac{1}{6}$$

• $$\frac{2}{6}$$
  

• $$\frac{3}{6}$$

• $$\frac{4}{6}$$
  

Multiple Choice

What is the probability that when I spin this spinner, I land on purple?

• $$\frac{1}{6}$$

• $$\frac{2}{6}$$
  

• $$\frac{3}{6}$$

• $$\frac{4}{6}$$
  

Multiple Choice

What is the probability that when I spin this spinner, I land on red, blue or yellow?

• $$\frac{1}{6}$$

• $$\frac{2}{6}$$
  

• $$\frac{3}{6}$$

• $$\frac{4}{6}$$
  

Multiple Choice

What is the probability that when I spin this spinner, I land on red, blue or yellow?

• $$\frac{1}{6}$$

• $$\frac{2}{6}$$
  

• $$\frac{3}{6}$$

• $$\frac{4}{6}$$
  

Multiple Choice

In the spinner, how many outcomes are there? 

(Hint: how many numbers are shown?)

• 4

• 6

• 8

• 10

Multiple Choice

In the spinner, how many pieces are coloured red?

• 1

• 2

• 3

• 4

Multiple Choice

What is the probability that when I spin this spinner, I land on red?

• $$\frac{1}{8}$$

• $$\frac{2}{8}$$
  

• $$\frac{3}{8}$$

• $$\frac{4}{8}$$
  

Sample Space

• The sample space of an experiment is the list of all possible outcomes.

• We use curly brackets { } or regular brackets ( ) to list the sample space.

• E.g. the sample space for tossing a coin: {heads, tails}

• E.g. the sample space for rolling a dice: {1, 2, 3, 4, 5, 6}

Multiple Choice

What is the sample space for tossing a coin?

• {heads}

• {tails}

• {heads, tails}

• {1, 2, 3, 4, 5, 6}

Multiple Choice

What is the sample space for the spinner shown?

• {yellow}

• {yellow and blue}

• {red and green}

• {yellow, blue, green, red}

Multiple Choice

What is the sample space for selecting a marble at random?

• {yellow}

• {green, red, blue}

• {yellow, blue}

• {yellow, green, red}

Multiple Choice

What is the sample space of this spinner?

• {green, blue, red, yellow}

• {blue, red, yellow}

• {green, blue, red}

• {green, pink, red, yellow}

Poll

How well do I understand Probability so far?

• I have no idea

• I understand this first lesson

• I sort of get it

Open Ended

Write three things you learnt from this lesson.

Multiple Choice

Probability is ...

• the chance that some event will occur.

• a game that involves coins.

• a guarantee.

Multiple Choice

Probability can be written as ...

• a fraction

• a decimal

• a percent

• all of the above

Multiple Choice

Describe the likelihood of an event with the probability of 1.

• certain to happen

• impossible to happen

• unlikely to happen

• equally likely as not to happen

Multiple Choice

The probability of an event occurring is a number between 0 - 1

• True

• False

Multiple Choice

What is an outcome?

• The result of an experiment

• The chance or likelihood of an event

• A fraction, decimal, or a percent

• An activity that gives various results

Multiple Choice

What is sample space?

• a process with an uncertain result

• a possible result of an action

• a list of all possible outcomes of an event

• a single outcome or group of outcomes

Multiple Choice

What is the sample space for the jar of marbles?

• {red}

• {red, yellow, green, blue}

• {red and yellow}

• {red and green}

Multiple Choice

What is the sample space for choosing 1 jelly bean from a jar of 4 red, 7 blue, and 2 green jellybeans?

• {4, 7, and 2}

• {red, blue, green}

• {2 green}

• {4 red}

Multiple Choice

What is the P(red)? Hint: What is the probability that the spinner will land on red?

• 0

• 1/2

• 3/4

• 1

Multiple Choice

Probability can be written as ...

• a fraction
• a decimal
• a percent
• all of the above

Multiple Choice

A likely chance event is closer to what number?

• 0
• 1
• .5
• 100

Multiple Choice

An unlikely chance event is closer to what number?

• 0
• 1
• 2
• 3

Multiple Choice

What is the probability of flipping a coin and getting heads?

• 1/2
• 1/3
• 1/4
• Never, Tails never fails.

Multiple Choice

What is the probability of spinning the spinner and having it land on RED?

• 33%
• 50%
• 12%

Multiple Choice

Is the spinner more likely or less likely to land on green than yellow?

• more likely
• less likely

Multiple Choice

If you were to roll the die one time what is the probability of it landing on a 2?

• 2 out of 6
• 2 out of 2
• 1 out of 6
• 1 out of 1

Multiple Choice

What is the probability of selecting an orange candy?

• 0%
• 25%
• 50%
• 100%

Multiple Choice

Find the probability of rolling a 7 on a single die.

• 1/6
• 7/6
• 0
• 7/7

Multiple Choice

What is the probability of spinning an even number?

• 1/6

• 2/6

• 3/6

• 4/6

Multiple Choice

What is the probability of spinning red?

• 0

• 1/2

• 3/4

• 1

Multiple Choice

Choose the correct answer to fill in the blank below:      
Sam  flips a coin  4 times.    

He is  ________________ ________________ to flip heads on his next turn  as he is to flip tails.  
   

• equally likely 
• most likely
• least likely

Multiple Choice

Which of the following will correctly complete the following statement. Probability, when written as a fraction, will . . .

• Never be 0

• Sometimes be greater than 1

• Always be between 0 and 1

• Will never be equal to 1

Multiple Choice

If you select a marble without looking, how likely is it that you will pick a black one?

• certain

• probable

• unlikely

• impossible

Multiple Choice

If you select a marble without looking, how likely is it that you will pick a black one?

• certain

• probable

• unlikely

• impossible

Multiple Choice

If you select a marble without looking, how likely is it that you will pick a black one?

• certain

• probable

• unlikely

• impossible

Multiple Choice

If you select a marble without looking, how likely is it that you will pick a white one?

• certain

• probable

• unlikely

• impossible

Multiple Choice

An outcome with the probability of 19/20 would be described as _.

• Certain

• Likely

• Unlikely

• Impossible

Multiple Choice

Probability that falls between the 0 and 1/2 would be described as ....

• Likely

• Evens

• Silly

• Unlikely