The angles of a triangle are in A.P. such that the greatest is 5 times the least. Find the angles in radians.

Let the angles of the triangle be (a – d) °, a° and (a + d) °.


We know that the sum of angles of triangle is 180°.


a – d + a + a + d = 180°


3a = 180°


a = 60°


Given greatest angle = 5 × least angle





60 + d = 300 – 5d


6d = 240


d = 40


Hence, angles are:


(a – d) ° = 60° – 40° = 20°


a° = 60°


(a + d) ° = 60° + 40° = 100°


Angles of triangle in radians:





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