It is given that the circumferences of two concentric circles forming a ring are 88 cm and 66 cm respectively and we need to find the width of the ring.
It is given that the circumference of the larger circle having radius say r1 is 88 cm. Therefore,
2πr1 = 88
⇒ r1 = 14cm
Similarly, the circumference of the smaller circle having radius say r2 is 66 cm. Therefore,
2πr2 = 66
⇒ r2 = 10.5cm
It is known that for two concentric circles, the width is equal to the difference in the radius of the circles. Mathematically,
w = r1 − r2, where
w is the width,
r1 is the radius of the larger circle and
r2 is the radius of the smaller circle.
On substituting the given value, we get the width as
⇒ w = r1 − r2
⇒ w = 14−10.5
⇒ w = 3.5
Hence, the width of the ring is 3.5.
