Puzzle 20 : Shrinking genie

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 This genie is not in a bottle but in a belt.


Genie in a belt

A magic rectangular belt always shrinks its length to 1/2 and width to 1/3 whenever its owner wishes something. After three such wishes, its surface is now 4 cm2. What was the original length, if the original width was 9 cm?


You can find the solution here.

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