Why do this problem?
is a more challenging version of How Many Pieces?
and can be approached in similar ways. If you tried How Many Pieces?
visually with your class, you may like to introduce this problem in a more practical way and vice versa.
The longer length of the pieces of string in this version make it slightly harder to solve.
Children may enjoy making up their own string patterns for a partner to work out the number of pieces used. It is quite a challenge to draw the patterns convincingly.
You might like to read the article Celtic Knotwork Patterns
and share some of the ideas with your class, particularly the tips for drawing knots!
Can you can follow a piece of string just by looking?
Why don't you use a different coloured pencil to trace over each new loop of string?
Can you explain how you decided on the number of loops there are?
Suggest staying with the simpler problem How Many Pieces?