Puzzle 109 - Magic belt

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There is a magic belt. When ever the wizard utters a spell its length reduces to half its original length and width reduces to 1/3 of its original width. 

The original width was 9 cm.

After the wizard invoked the spell 3 times, the area of the belt now is 4 cm2 .

What was the original length of the belt? 

 

Find the solution here.  

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