circumference of the outer circle = 2πr = 2π(6) = 12π
circumference of the outer arc = 120/360 x 12π = 12.57cm
circumference of the inner circle = 2πr = 2π(5) = 10π
circumference of the inner arc = 120/360 x 10π = 10.47 cm
Difference in length = 12.57 - 10.47 = 2.1cm (1 d.p.)
Answer: 2.1cm
