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'Count the Crayons' printed from https://nrich.maths.org/
Imagine grouping the items into 10s.
Here is an example which leads me to believe that there are approximately 50 items in this picture. To be on the safe side, I will give a range as my answer and say that I think there are between 40 and 60 items.
PICTURE
Can you use a similar approach? Can you use a different approach?