Basic Probability

Basic Probability

What is probability?

Probability is the measurement of chance of an event occurring. We can use words or fractions to express probability.

Impossible

This occurs when the outcome doesn’t exist. It would be impossible to spin a green on this spinner.

Multiple Choice

Which example shows a result that is impossible?

• The sun will rise tomorrow

• It will snow today

• You will have two birthdays this year

• You will roll a 4 on a die

Unlikely

This occurs when you have less than a ½ chance of an event occurring. It is unlikely you will spin a yellow since such a small section of the spinner is yellow.

Multiple Choice

Which picture shows an unlikely probability of getting blue?

Likely

This occurs when you have more than a ½ chance of an event occurring. It is likely that you will spin a blue since over half of the spinner is blue.

Multiple Choice

Which picture shows a likely chance of getting green.

Certain

This occurs when all the possible choices are selected. It is certain you will spin blue since that is the conly color on the spinner.

Multiple Choice

Which example shows a certain outcome?

• You will roll a six on a die

• A coin will land on either heads or tails when tossed

Multiple Choice

What is the probability that the spinner will land on yellow?

• certain

• likely

• unlikely

• impossible

Multiple Choice

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

• certain

• likely

• 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

How likely is it that I will choose a black marble?

• Certain

• Likely

• Unlikely

• Impossible

Multiple Choice

How likely is it that summer will come?

• Certain

• Likely

• Unlikely

• Impossible

• Equally likely

Multiple Choice

How likely is it that I will see a dinosaur tomorrow?

• Certain

• Likely

• Unlikely

• Impossible

• Equally Likely

Multiple Choice

Jazlyn has 4 quarters, 10 dimes, and 3 nickels in her wallet. What is the likelihood of her choosing a penny?

• certain

• likely

• unlikely

• impossible

Multiple Choice

Evan has 6 red marbles and 2 green marbles in a bag. What is the likelihood of him choosing a green marble?

• certain

• likely

• unlikely

• impossible