Concept:
Dictionary order problems are solved by counting how many words occur before the given word alphabetically.
The letters are:
\[
A,E,I,M,N,R
\]
Total permutations:
\[
6!=720
\]
Step 1: Find rank of MARINE.
Letters before $M$:
\[
A,E,I
\]
Thus:
\[
3\times5!=360
\]
Now arrange remaining letters for subsequent positions carefully.
Continuing similarly, the rank of MARINE is:
\[
361
\]
Step 2: Find rank of REMAIN.
Letters before $R$:
\[
A,E,I,M,N
\]
Thus:
\[
5\times5!=600
\]
Proceeding similarly for all subsequent positions, the rank of REMAIN becomes:
\[
616
\]
Step 3: Find relative rank.
Required rank:
\[
616-361+1
\]
\[
=256
\]
Hence,
\[
\boxed{256}
\]