Q2 of 18 Page 173

In the same circle, what is the length of an arc of central angle 25° is 4 centimetres.

i) In the same circle, what is the length of an arc of central angle 75°?


ii) In a circle of radius one and a half times the radius of this circle, what is the length of an arc of central angle 75°?

In a circle of radius r,


If central angle = x°


Length of arc =


Here,


x = 25°


r = 4 cm


Length of arc =




i) Here,


x = 75°


r = 4 cm


Length of arc =



ii) Here,


x = 25°


r = 1.5 × 4 = 6 cm


Length of arc =



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