In the diagram, O is the center of the circle, ∠MON = 80o, ∠LMO =...

In the diagram, O is the center of the circle, ∠MON = 80^o, ∠LMO = 10^o and ∠LNO = 15^o. Calculate the value of x

The correct answer is: C

Reflex + ∠OML + ∠ONL + ∠NLM = 360
280^o + 10^o + 15^o + x = 360^o => 305^o + x^o = 360^o
x = 360^o - 305^o = 55^o