Lesson Page
Uncertainty 



A
possible outcome
is something that has a chance of happening. One way to record outcomes
is by making a tally table.
Sally wrote R,
S, and T on 3 pieces of paper and put them into a bag. Then she
picked a letter at random, tallied the outcome, and put the letter
back into the bag. 
There are 3 possible outcomes: R,
S, and T. 



Outcomes after 10
Tries 
After each try,
Sally put the letter back into the bag. So for each try, the
probability of picking R was
1 out of 3. She has the same chance of picking one of the
letters each time. She
cannot be sure of picking any one letter. 
Letter 
Tally 
R 
lll 
S 
lll 
T 
llll 

An
event is most likely
to happen if it has a
greater chance of happening than other events.
An event is
least likely to
happen if it has a lesser
chance of happening than other events. 

The outcomes for
this spinner are 1, 2, or 3.
The spinner is
most likely to land
on number 3.
The spinning is
least likely to land
on numbers 1 or 2. 
Spinning one of the numbers on the spinner. List all possible outcomes.

1, 2, 3, or 4 
Flipping a coin. List all possible outcomes.

heads or tails 

Remember:
The probability
changes as the number of possible outcomes changes. 
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Practice!
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