94. Three lines AB, CD and EF intersect each other at O. If ∠AOE = 30° and ∠DOB = 40° (Fig. 5.51), find ∠COF.
110°
∠AOE + ∠COF + ∠DOB = 180°. Substituting values: 30° + ∠COF + 40° = 180° ⇒ ∠COF = 110°.