Language of probability
The sun will rise tomorrow
Certain
A spinner has 4 equal sections.
What is the probability of landing in one specific section?
1/4
What probability number represents an event that is equally likely to happen or not happen?
0.5
A coin is tossed 20 times and lands on heads 7 times.
What is the relative frequency of heads?
7/20
Probability
A measure of how likely an event is to happen.
Written as a number between 0 and 1.
The probability of flipping a coin and getting heads.
Even chance
A die is rolled.
What is the probability of rolling a number greater than 4?
2/6 OR 1/3
A spinner has 8 equal sections numbered 1 to 8. What is the probability of landing on a prime number?
4/8 (1/2)
State whether this is theoretical or observed probability: " 6 of the 20 marbles in the bag were green"
Theoretical
Experiment
A test or action where the outcome is unknown.
A class has 12 boys and 18 girls.
If a student is picked at random, what is the probability of it being a girl?
Likely
From digits 0–9, what is the probability of selecting an even number?
5/10
A six sided did is rolled 24 times. How many times should it be expected to roll a 1?
4 times
The probability of the local football team winning their grand final is 0.36. What is the probability that they won't win the grand final?
0.64
outcome
A possible result of an experiment.
A bag contains 3 red, 2 blue, and 5 green marbles.
What are the chances of drawing a red marble?
Unlikely
A die has 6 faces.
what is the possibility of rolling a 1 or 2
2/6
the numbers from 2 to 10 are written on separate cards. one card is chosen at random. what is the probability that the number is less than 6?
4/9
A bag of mixed lollies is sampled 25 times.
10 times the result was chocolate.
What is the relative frequency of chocolate
47/100
Relative Frequency
Probability based on what actually happened in an experiment.
A twelve-sided die is rolled. what are the chances of the outcome being eight or higher?
Unlikely
23 marbles are in a bag and 4 are black. one is picked from the bag without looking. What is the probability that the marble is not black?
19/23
A bag contains 28 red marbles , 27 blue marbles and 26 black marbles. What is the probability of drawing a blue marble?
27/81
A student tosses two coins 50 times.
They get “two heads” 11 times. Relative frequency of getting two heads
11/50
Theoretical Probability
Probability based on maths and what should happen.