OG question
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One thing can be made out from the stem - AB = OC = OB = radius
Hence Triangle ABO becomes an isoceles triangle....
Statement I : COD = 60 degrees...Hence angle COA = 180-60 = 120 degrees
CBO = Angle BAO + Angle BOA (extrerior angle = sum of remote interior angles) = 2x
Hence angle BAO = BOA = x
Now BOC + BOA = 120
So 180-4x+x = 120
3x = 60; hence x = 20
Hence sufficient
Statement II : If BCO = 40...Then BCO = CBO = 40
Hence ABO = 140 and BAO = BOA = 180 - 140/ 2 = 20
hence sufficient
Hence Triangle ABO becomes an isoceles triangle....
Statement I : COD = 60 degrees...Hence angle COA = 180-60 = 120 degrees
CBO = Angle BAO + Angle BOA (extrerior angle = sum of remote interior angles) = 2x
Hence angle BAO = BOA = x
Now BOC + BOA = 120
So 180-4x+x = 120
3x = 60; hence x = 20
Hence sufficient
Statement II : If BCO = 40...Then BCO = CBO = 40
Hence ABO = 140 and BAO = BOA = 180 - 140/ 2 = 20
hence sufficient