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## 'Missing Multipliers' printed from http://nrich.maths.org/

The multiplication square below has had all its headings and
answers hidden. All of the headings are numbers between 2 and 12,
and no heading appears twice horizontally or
vertically.

By revealing some of the answers, can you work out what the
headings must be?

This text is usually replaced by the Flash movie.

What is the smallest number of answers you need to reveal in order
to work out the missing headers?

Can you describe a strategy that allows you to complete
the Level 3 challenge most of the time?

Can you suggest any reasons why your strategy might not always
work?

Once you have a strategy for completing Level 3, here are some more
Missing Multiplier challenges you might like to try:

You might also like to try some challenges which include negative
numbers.

A 4 by 4 grid, using multipliers from
-4 to +4
A 6 by 6 grid, using multipliers from -6
to +6