Each of the questions below consists of a question and two statements numbered I and II given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. Read both the statements and give answer
1) if the data in statement I alone are sufficient to answer the question while the data in statement II alone are not sufficient to answer the question.
2) if the data in statement II alone are sufficient to answer the question while the data in statement I alone are nod sufficient to answer the question.
3) if the data either in statement I alone or in statement II alone are sufficient to answer the question.
4) if the data even in both statements I and II together are not sufficient to answer the question.
5) if the data in both statements I and II together are necessary to answer the question.
How old is Mohan?
I. Mohan is twice as old as he was 15 years ago.
II. Mohan is thrice as old as he was 20 years ago.

Explanation

4