The mean of three numbers x, y and z is x.

What is the mean of y and z?

This problem is taken from the UKMT Mathematical Challenges.

You can find more short problems, arranged by curriculum topic, in our short problems collection.

Mathematical reasoning & proof. Inequalities. Expanding and factorising quadratics. 2D shapes and their properties. Simultaneous equations. Circle properties and circle theorems. Generalising. Regular polygons and circles. Creating and manipulating expressions and formulae. Polynomial functions and their roots.