Read the following question and decide which of the statements is sufficient to answer the question.
Question:
The average marks of X, Y and Z is 180. What is X's mark?
Statements:
I. Y and Z together scored 50 marks.
II. X and Z together scored 60 marks.
1
Both statements I and II together are sufficient to answer the question
2
Statement II alone is sufficient while I alone is not sufficient to answer the question
3
Either statement I or II is sufficient to answer the question
4
Statement I alone is sufficient while Il alone is not sufficient to answer the question