Happy Black Friday to my American friends.

While you're waiting in the queues for the shops to open, how about dropping me a silly question? Unfortunately, I can't tell you what time Macy's opens, but ask me one about maths!

## Colin

Colin is a Weymouth maths tutor, author of several Maths For Dummies books and A-level maths guides. He started Flying Colours Maths in 2008.
He lives with an espresso pot and nothing to prove.