His inimitable style has helped countless children develop an interest in science and maths.
Johnny Ball came into our studio to talk about his new book Think of a Number
And, he set us a puzzle!
If you missed the details you can click on the link below to see the puzzle again.
And the answer is at the bottom of this page.
Johnny said that his aim is to get children enthusiastic about maths and numbers for their own sake.
I think we spend too much time worrying about kids and maths
He feels that children will enjoy maths if we make it more fun and he advises parents to play maths games with their children, such as dominoes.
Here are the details of the maths puzzle set by Johnny Ball
Three friends share a meal at a restaurant.
The bill comes to £30
They divide it equally, paying ten pounds each.
But the waiter realises he's made a mistake and should have charged £25.
He gives the friends five pounds back .
They decide to take one pound each and give the waiter a £2 tip
So, each person ends up paying £9 and the waiter keeps £2, making £29 in total.
What happened to the missing £1?
There is no missing pound.
You don't add the £2 to the £27 they've paid because the £2 is already included in that £27 - The £2 features twice
The actual sum is the £27 plus the £3 they got back, which brings you to the original £30.
The premise of the question is false!