A, B, C, D and E are standing in a line facing North. E is standing 40 meters left to B. A is standing 20 meters left to C. D is standing 20 meters right to E and 50 meters right to C. Where is B standing from D?

According to question,
If P is sitting second to the left of S and Q is sitting third to the right of R. T sits immediate right of S, Q is not on immediate right or left of S.
It is clear that , S is sitting to the immediate right of R.
Sitting arrangement :-

According to question,
We can draw a figure , in which A is on the right of B, E is on the left of B, but to the right of C. If A is on the left of D .
From given figure it is clear that , B is in the middle.
Sitting arrangement :-

According to question,we have
Rashi's position = 15th from the left
Ramesh's position = 29th from the right
After interchanging their positions ,
Rashi's position = 26th from left
? Total number of students = Rashi's position + Ramesh's position - 1
Total number of children in the row = 26 + 29 ? 1 = 54
As shown in figure -

According to question,
We can draw a figure , in which A and B are sitting face to face. D is not sitting next to A but can see the facial expression of A clearly. B is talking to C who is sitting opposite to him.
From given figure it is clear that , A and C are sitting together.
Sitting arrangement :-

Draw a figure on the basis of above given question ,
Y is at the left of X, W is sitting at the right of Z. V is sitting at the right of X and W is sitting at the left of Y. If Z is sitting at one end of the row .
From figure , It shows that Y is in the middle.
Sitting arrangement :-

According to question,
We can draw a figure , in which G is between A and E .F and A have one boy between them . E and C have two boys between them . D is to the immediate .C and B have three boys between them.
From given figure it is clear that , E is second from left.
Sitting arrangement :-

Draw a figure on the basis of above given question ,
P sits next to S but not to T. Q is sitting next to R who sits on the extreme left corner.
As shown in figure , P sits to the left of S.
Sitting arrangement :-

Draw a figure on the basis of above given question ,
In which , D is on the left of C and B is on the right of E. A is on the right of C and B is on the left of D. If E occupies a corner position.
As shown in figure , D is sitting in the centre.
Sitting sequence :-

Draw a figure on the basis of above given question ,
A is to the right of C, but left of B. E is sitting left of C and right of D, who is sitting to the right of F.
As shown in figure , F and B are sitting at the two ends of the row.
Sitting arrangement :-

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