The diagram shows the first few squares of a ‘spiral’ sequence of squares. All but the first three squares have been numbered. After the first six squares, the sequence is continued by placing the next square alongside three existing squares – the largest existing square and two others. The three smallest squares have sides of length 1. What is the side length of the 12th square?
Select one option, then click Submit.
153
123
83
53
13
Select an option, then submit.
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