Think Academy is organising a Sport Day. Teacher Nicole wants to place the flag along the field. She needs to make sure that the flag are place in a consistant distance between $$2$$ flags. Lucy is curious about the distance between $$2$$ flags. Techer Nicole tells her that the distance between the 1\textsuperscript{st} and 4\textsuperscript{th} flag is $$9\text{m}$$. What is the distance between the 1\textsuperscript{st} and 9\textsuperscript{th} flag? 
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