There are some marbles in a jar.
18\displaystyle \frac{1}{8}81 of the marbles are green.
The rest of the marbles are yellow.
Write the ratio of the number of green marbles to the number of yellow marbles.
Give your answer in the form 1:n1 : n1:n
64 exam-style questions on Edexcel GCSE Maths Writing and Simplifying Ratio. Each one has a worked solution and a mark scheme showing where the marks go.