Thank goodness its Friday! We've worked hard all week and here's an opportunity to really test those brains.
Below are three problems; you can choose one, two or all three to complete - it's up to you. Remember, I'm not just interested in the correct answer. Having a go, jotting some ideas down or even drawing a picture are all sensible approaches to problem solving.
So give at least one problem a bash and send in what you come up with. Good luck!