I is the incentre of a triangle ABC. If ∠ABC = 65°

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I is the incentre of a triangle ABC. If ∠ABC = 65° and ∠ACB = 55°, then the value of ∠BIC is

1. 130°
2. 120°
3. 140°
4. 110°

Correct Option: B

Firstly , We draw a figure of triangle ABC whose I is incentre ,

∠IBC =	1	∠ABC =	65	= 32.5°
	2		2

∠ICB =	1	∠ACB =	55	= 27.5°
	2		2

We know that , ∠BIC + ∠ICB + ∠IBC = 180°
∴ ∠BIC = 180° - 32.5° - 27.5° = 120°