The given information is:
- The area of the sector of the circle is 31.2 cm^2.
- The exterior of the sector angle is 256°.
The area of the sector is given by the formula:
Where theta is the sector angle and r is the radius of the circle.
The whole circle measures 360°, so the sector angle can be found as follows:
Now, replace theta and the area value in the formula to solve for r:
The radius of the circle is 5.9 cm.