Question 1148864
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In each of the isosceles right triangles, the hypotenuse is 1/8 of the perimeter of the octagon, which is 20/8 = 2.5cm.<br>
The sides of an isosceles right triangle are in the ratio 1:1:sqrt(2), so each leg of each isosceles triangle has a length 2.5/sqrt(2), or 1.25*sqrt(2).<br>
The perimeter of the star is the combined perimeter of both legs of all the isosceles triangles, which is 16*(1.25*sqrt(2)) = 20*sqrt(2).<br>
ANSWER: 20*sqrt(2) cm