A drawer contains black socks and white socks.
The ratio of black socks to white socks is 2:12:12:1.
Two socks are taken at random from the drawer.
The probability that both socks are white is 112\displaystyle \frac{1}{12}121.
Calculate the total number of socks in the drawer before any were removed.
28 exam-style questions on Edexcel GCSE Maths Probability Equation Questions. Each one has a worked solution and a mark scheme showing where the marks go.