Steve is making a circular shield with a radius of 11 inches for a school play. What approximate length of cardboard does he need to make the outer border of the shield?

To find the length of cardboard needed to make the outer border of the shield, we first need to find the circumference of the circle.

The formula for calculating the circumference of a circle is:
Circumference = 2 * π * radius

Plugging in the radius of 11 inches:
Circumference = 2 * π * 11
Circumference ≈ 2 * 3.14159 * 11
Circumference ≈ 69.1157 inches

Therefore, Steve would need approximately 69.1157 inches of cardboard to make the outer border of the shield.