Question

There are seven persons up on a ladder, A, B, C, D, E, F and G (not in that order). A is further up than E but is lower than C. B is in the middle. G is between A and B. E is between B and F. If F is between E and D, the person on the bottom step of the ladder will be

Answer 1

just foprget about order.very easy

A_B_C_D_E_F_G
since B is in the middle
A_C_D_B_E_F_G
since A is further up than E but less than C
C_A_D_B_E_F_G
G is in the middle of A and B so
C_A_G_B_D_E_F
since e is between B and F
C_A_G_B_E_F_D
the person who is the last is D
so our final sequence is
C_A_G_B_E_F_D

Answer 2

There are two answers:  E  or   D.

Given B is in the middle of the ladder.  So there are 3 persons higher than B and 3 are lower than B.

Given G is in between A and B.  So  A < G < B.  or,    B < G < A.
given  E is in between B and F.  So  B < E < F    or,    F < E < B.
given  F is in between E and D,  so  E < F < D    or      D < F < E

Given E < A < C
If we choose,  A < G < B,  then      E < A < G < B.   ie., 3 persons lower than B. 
   The person E is on the lowest step.

Hence,  the remaining C , D and F are above B.  Hence, we choose, B < E < F.  Since, E < F then  we choose  E < F < D.   So B <  E < F < D.
So the order is E < A < G < B < E < F < D.
======================================

There is a second solution.
given E < A < C.

Now, suppose we choose,  B < G < A.
     Then B < G < A < C.  Hence, D, E and F are  below B. 
 So we choose,   F < E < B and  D < F< E.

Thus the order is :  D < F < E < B < G < A < C
hence, the person D is on the bottom step of the ladder.