Coaching Centre
Probability
Sample spaces, equally likely outcomes, probability as a fraction, decimal or percentage, complementary events and the probability scale.
Theoretical probability
The sample space is the list of all outcomes. For one die it is $\{1, 2, 3, 4, 5, 6\}$.
A letter is chosen at random from the word PARRAMATTA. Find $P(\text{A})$.
The probability of rain tomorrow is $0.35$. Find the probability it does not rain.
A letter is chosen from PARRAMATTA. Find $P(\text{A})$ as a fraction.
$4$ out of $10$.
$P(\text{rain}) = 0.35$. Find $P(\text{no rain})$.
$1 - 0.35$.
A die is rolled. Find $P(\text{even})$.
$3$ out of $6$.
A card is drawn from a standard deck of $52$. Find $P(\text{king})$.
$4$ out of $52$.
A card is drawn from a standard deck. Find $P(\text{heart})$.
$13$ out of $52$.
A die is rolled. Find $P(\text{not a } 1 \text{ or } 2)$.
$4$ out of $6$.
Which is impossible?
A die only shows $1$ to $6$.
A bag has $5$ red, $4$ blue and $3$ green balls. Find $P(\text{not red})$.
$7$ out of $12$.
New numbers every time. Keep going until you get five in a row.