Q9 of 25 Page 276

The ratio of two angles subtended by two arcs of unequal lengths at the centre is 5:2 and if the sexagesimal value of the second angle is 30°. Then let us determine the sexagesimal value and the circular value of the first angle.

let the length of arcs be 5x and 2x

Let r be the radius of the circle


…[1]


Let θ be the angle subtended by the arc of length 5x.


…[2]


By dividing eq. [1] and eq. [2]





⇒ θ = 75°


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