Answer:
The person standing at the fourth position is Maria.
Explanation:
We are given that,
There are four students standing in line for lunch namely, Tim, Paco, Maria and Jenny.
Now, as Jenny is standing between Paco and Maria.
So, we have the possibility, P J M.
Also, as Paco is standing at an odd numbered position.
So, we have, either Paco stands at 1st or 3rd position.
Further, it is given that, Tim is not standing on either end of the line.
So, we get, the possibilities,
P J T M and M J P T.
But, in M J P T, T=Tim is standing at the end of the line, which is not possible.
So, the final positioning is given by, P J T M.
Hence, the person standing at the fourth position is Maria.