The inner and outer radii of two concentric circles are 6.7 cm and 9.5 cm, respectively. What is the difference between their circumferences (in cm) ? Take π = 22/7

Explanation

Given: Inner radius of concentric circles = 6.7cm Outer radius of concentric circles = 9.5 cm Formula: Circumference of circle = 2πr Calculation: Circumference of small circle = π × 2 × 6.7 = 13.4π Circumference of big circle = π × 2 × 9.5 = 19π ∴ Difference between their circumference = (19 - 13.4)π = 5.6 × 22/7 = 17.6 cm