Year 10 Mathematics
Probability Study Notes
PROBABILITY
Probability is the mathematics of chance
or likelihood of something happening
EXPERIMENTAL PROBABILITY
Experimental Probability of an event =
number of times this event occurred
total number in sample
THEORETICAL PROBABILITY
If each possible outcome is equally likely then
Probability of an event =
Number of ways the event can occur
Number of ways all events can occur
RANGE OF PROBABILITY
The probability P(E) of any event E occurring must lie in the range
0 ≤ P(E) ≤ 1
PROBABILITY OF A CERTAIN EVENT
The probability of an event CERTAIN to happen is 1
P(sure thing) = 1
PROBABILITY OF AN IMPOSSIBLE EVENT
The probability of an event which can not happen is 0
P(impossibility) = 0