Question 1151517
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<pre>

Let x be the side length of the square piece of paper.


Then the folded piece of paper has the side lengths x , x/2, x and x/2,  so its perimeter is


    {{{x}}} + {{{x/2}}} + {{{x}}} + {{{x/2}}} = 34.5,

    3x               = 34.5,

     x               = 34.5/3 = 11.5 cm.    <U>ANSWER</U>
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Solved.