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These sixteen children are standing in four lines of four, one behind the other. They are each holding a card with a number on it.
children holding numbers
Each child in blue is holding a number which is four more than the child in the same row wearing red.
The children in yellow shirts each have a number which is double the number of the child in the same row wearing red.
Some of the numbers that the children in red, blue or yellow shirts are holding have got rubbed off. What should the numbers be?
Can you work out how the numbers that the children in green are holding have been worked out? What are the two missing numbers?
If there was another row of four children standing behind the fourth row, what numbers would they be holding?