Answer:
9.55 cm
Explanation:
A quadrant of a circle is 1/4 of a circle.
Since the curved edge is 15 cm, a full circle would be 60 inches.
60/Pi = diameter
diameter = 60/3.14 = 19.11 cm
diameter/2 = radius
radius = 19.22/2 = 9.55 cm which is the length of a straight edge.