It's an odd world

Can you put the numbers 1 to 9 in the diagram so that the difference between each pair of joined numbers is odd?

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This challenge is to find as many ways as possible of making 12 using three number cards and the add, subtract and multiply signs.

This time you can decide the total for the sides of the triangle.

Investigation looking at possibilities when adding the digits from 1 to 5.

A development of the 'Caterpillar investigation' but using multiples of 10. Great for practising addition.