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International Baccalaureate · PYP 1

Chance

⌚ ~66 min ▢ 6 blocks ✓ 26 exercises ➣ Prerequisites : Sorting, Picture Graphs and Chance
I What Can Come Out?
Method — Everything That Can Come Out, and the Hoop
Before we pick, roll or spin, we look at everything that can come out: all the counters in the bag, all the faces of the die, all the parts of the spinner.
For a sentence about the result, such as “the die shows more than 4 dots”:
  1. put in a hoop everything that makes the sentence true;
  2. compare the hoop with everything that can come out: if everything is in the hoop, it is certain; if only some of it is in the hoop, it is possible; if nothing is in the hoop, it is impossible.
Figure
The hoop holds 2 of the 6 faces: some of them, not all. Getting more than 4 dots is possible.
Example
This spinner has 4 equal parts: 2 red parts, 1 blue part and 1 yellow part. We spin it once.
Figure
What can come out? Which parts make “the pointer stops on red” true? And “the pointer stops on green”?

Everything that can come out: the 4 parts of the spinner.
Figure
The hoop for red holds the 2 red parts: some of the 4 parts, not all. The pointer stopping on red is possible.
The hoop for green stays empty: no part is green. The pointer stopping on green is impossible.

Skills to practice
  • Showing Everything That Can Come Out
  • Filling the Hoop
II Certain, Possible or Impossible?
Definition — Chance
Some things we do, like flipping a coin or rolling a die, can end in more than one way, and we cannot know which one before. We call this a random experiment.
The chance of something tells us if it is sure to happen, might happen or might not, or can never happen. We use special words to describe this chance.
  • Impossible means something can never happen.
    Example: We roll a die whose faces show 1 to 6 dots. Getting 7 dots is impossible.
  • Possible (or “maybe”) means something might happen or might not.
    Example: We pick a counter from a bag of red and blue counters. Getting a red counter is possible.
  • Certain means something will always happen.
    Example: We pick a counter from a bag of red counters only. Getting a red counter is certain.
Skills to practice
  • Judging Everyday Events
  • Picking at Random
  • Building the Bag
III Going further
Skills to practice
  • Writing Chances with Numbers
  • Quiz