Question 1159975
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Let "n" be the number of sides (= vertices).


Then

    n*160 = (n-2)*180  degrees

    160n  = 180n - 360

    360   = 180n - 160n

    360   = 20n

       n  = {{{360/20}}} = 18.


The sum of all interior angles = (18-2)*180 = 16*180 = 2880 degrees.    <U>ANSWER</U>
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Solved.