4. A wire is bent to form a square of side 22 cm. If the wire is rebent to form a circle, its radius is
(a) 22 cm
(b) 14 cm
(c) 11 cm
(d) 7 cm
Perimeter of square = \(4 \times 22 = 88\,\text{cm}\).
This is the circumference of the circle: \(2 \pi r = 88\).
\(r = \dfrac{88}{2 \pi} = 14\,\text{cm}\).