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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.
R S T

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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