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A Conversation Piece


Divide 6 469 693 230 by the first ten prime numbers and you'll get the most beautiful and most magic of all numbers. What is it?

Why do this problem?

This problem offers a lot of practice of division as well as revision of ideas about prime numbers in a situation in which children want to get to the answer - much more fun than a page of calculations but just as much practice. It requires a calculator unless someone really relishes long division!

Key questions

Have you made a list of the first ten prime numbers?
Remember that $1$ is not a prime number.
Which number are you going to divide by first?
How will you know whether you have divided by that number already?

Possible extension

Learners who find it easy could be encouraged to invent their own similar problems which will give them practice with multiplication as well as division.