Since it is rolled via it's length, the circumference of the circle must be 50 cm.
The formula for the circumference is 2[tex] \pi r[/tex]
50 = 2[tex] \pi r[/tex]
25 = [tex] \pi r[/tex]
7.95774715459 = r
Your radius should be approximently 7.96 cm. Hope this helps!
