Introduction to probability

A bag contains red counters, blue counters and yellow counters. Altogether, there are 60 counters in the bag. The probability that a counter chosen at random from the bag is red is $\dfrac{2}{5}$. The probability that a counter chosen at random from the bag is blue is $\dfrac{5}{12}$.

May/June 2015

A bag holds red and blue pegs. There are $40$ pegs altogether in the bag. The probability of picking out a red peg from the bag is $0.4$.

May/June 2017

Rowena spins two fair spinners, and each spinner is labelled 1 to 4. Her score is the product of the two numbers shown.

May/June 2017

A bag has coloured counters inside. One counter is chosen at random from the bag. The table gives the probabilities of selecting a counter of each colour.

May/June 2021

A fair spinner numbered from $1$ to $5$ is shown in the diagram. The score is whichever number the spinner stops on.

May/June 2024

A bag holds 11 balls. Of these, 5 are blue and 4 are yellow. The remaining balls are green. One ball is selected from the bag at random.

May/June 2025

A spinner may stop on red, green, yellow or blue. The table gives the probability attached to each result.

May/June 2025

There are exactly two white beads and one black bead in the bag. Two beads are then chosen at random without replacing them.

Oct/Nov 2019

The email counts received by $18$ students in a class on one Monday are shown.

Oct/Nov 2020

Some children note how many hours each of them spends watching television on one day. The results are: 1, 2, 2, 2, 6, 7, 7, 8, 10.

Oct/Nov 2025