List

Sharing Incomplete Solutions

There are a number of different ways in which you, as the teacher, might use NRICH solutions as part of the lesson itself and these are outlined in our Celebrating Solutions Feature.  

The tasks below have some published solutions which are not completely correct.  Challenge your learners to find what is not quite right in each one and to explain why, or how they know.

Inside Triangles
problem
Favourite

Inside Triangles

Age
5 to 7
Challenge level
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How many different triangles can you draw on the dotty grid which each have one dot in the middle?
School fair necklaces
problem
Favourite

School fair necklaces

Age
5 to 11
Challenge level
filled star filled star empty star
How many possible symmetrical necklaces can you find? How do you know you've found them all?
Reflecting Squarely
problem
Favourite

Reflecting Squarely

Age
11 to 14
Challenge level
filled star empty star empty star
In how many ways can you fit all three pieces together to make shapes with line symmetry?