U8 Lesson 1 Probability Intro Lesson

Probability

What does probability look like?

Basic Examples

​A coin has two possible outcomes:
heads, tails

The probability of a coin landing on heads is ½, 0.5, or 50%
The probability of a coin landing on tails is ½, 0.5, or 50%

​A number cube (dice) has six possible outcomes (shown above).

The probability of landing on...
the 1 is 1/6
the 2 is 1/6
the 3 is 1/6
and so on...

This spinner has 8 possible outcomes (8 sections).

The probability of...
landing on green is ⅜
landing on red is 2/8
landing on blue is 2/8
landing on yellow is ⅛

This bag has 11 possible outcomes (11 marbles).

The probability of picking a...
red marble is 5/11
blue marble is 2/11
green marble is 2/11
purple marble is 2/11

When we list all of the possible outcomes of an event, we call that the sample space.

​Sample Space

​Sample Space for rolling a number cube:

Match

Match the following events to their probabilities.

• flipping a coin and it landing on heads

• rolling a fair six-sided die and getting a 6

• selecting a card with a 13 on it from a standard deck of playing cards

• rolling a fair six-sided die and getting a 3 or a 4

• flipping a coin and it landing on heads or tails

as likely as not

unlikely

0

impossible

unlikely

1

certain

• $$\frac{1}{2}$$

  as likely as not

• $$\frac{1}{6}$$

  unlikely

• 0

  impossible

• $$\frac{2}{6}$$

  unlikely

• 1

  certain