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CTET Feb 2015 Paper 2 Maths & Science (L - I/II: Hindi/English/Sanskrit)

Option 4 : 135°

Solution:

Given: The sum of all interior angles of a regular convex polygon is 1080°.

Formula Used: The sum of all interior angles of the regular polygon is (n - 2) × 180; where n is the number of sides.

Calculation: using the above formulae, we get

⇒ (n - 2) × 180 = 1080°

⇒ n = 8

∴ measure of each of its interior angles = 1080°/8 = **135° **