let us discuss about various models in Row arrangement.
i) Persons facing North
ii) Persons facing South
iii) Two row arrangement (persons in one row face North and the other row face South).
iv) Persons in a row face different directions (North and South)
v) Persons in a row with vacant seat
vi) Two row with vacant seats
vii) Single row with distribution
(for eg: Eight persons sitting in a row likes different colours, relations, different ages, different professions and so on will be given)
This distribution can be combined with any of the models from (i) to (vi).
Points that are to be remembered while solving questions on Row arrangement:
1) The persons who are facing North will have the same directions as ours i.e., (their left is towards our left, their right is towards our right, directions – same).
2) The persons who are facing South will have opposite directions as ours i.e., their left is towards our right, their right is towards our left, directions are opposite).
3) The words Who / Which always refers to the immediately previous person / thing. For eg: A is to the left of D who is to the left of C, means here the word ‘who’ refers to D but not to A. The order is A D C.
4) The words And / But always refers to the first person with which the statement has started.
For eg: A is to the left of D but is to the right of C, means here the word "but" refers to A but not to D. The order is C A D.
5) In this left need not necessarily be immediate left and right need not necessarily be immediate right.
For eg: A is to the left of D doesn’t mean that A is to the immediate left of D. Whether A and D can be together or there could be some persons between A and D.
Now let us discuss about each model in Row arrangement with an example.
(v) Persons in a row with vacant seat:
Directions (1-5): These questions are based on the following information.
Seven persons A, B, C, D, E, F and G sit in a row of eight seats in which there is a vacant seat that is not at any end of the row. All are facing north and the distance between any two adjacent persons is same further it is known that. Only three persons sits between C and F. Neither C nor F sits adjacent to vacant seat. G sits second to the right of B and neither of them sit at any end of the row. A sits neither adjacent to vacant seat nor in between B and G. D sits to the right of A but not immediate right. F sits second to the right of D.
1. Who sits third to the left of G?
1) C 2) G 3) A 4) F 5) B
2. How many people sit between A and G?
1)None 2) One 3) Two 4) Three 5) Four
3. What is the position of B with respect to D?
1) Immediate left 2) Second to the left 3) Fourth to the left 4) Fourth to the right 5) Immediate right
4. Four of the following five are alike in a certain way hence form a group. Find the one which does not belong to that group?
1) AB 2) GC 3) EF 4) BG 5) DE
5. Who among the following are immediate neighbours of E?
1) D and F 2) G and D 3) A and C 4) B and G 5) C and D
Solutions for questions 1 to 5:
It is given that only three persons sit between C and F and F sits second to the right of D. Neither C nor F sits adjacent to vacant seat and vacant seat is not at any extreme end of the row. It can be shown as follows.
It is also given that D sits to the right of A but not immediate right. A does not sit adjacent to vacant seat. Hence cases (i), (ii) and (iii) gets eliminated. G sits second to the right of B and neither of them sits at any extreme end of the row. Hence case (iv) gets eliminated.
In case (v), B sits to the immediate left of C and G sits to the immediate right of C. A sits at the left end of the row and E sits to the immediate left of F. Hence the final arrangement is as follows.
1. A sits third to the left of G. Choice (3)
2. Two people sit between A and G. Choice (3)
3. B sits fourth to the left of D. Choice (3)
4. Except B and G remaining all pairs sit adjacent to each other. Choice (4)
5. D and F are immediate neighbour of E. Choice (1)
(vi) Two row with vacant seats:
Directions (6-10): These questions are based on the following information.
Ten persons sit in twelve seats in two rows each contains six seats. J, K, L, M and N are seated in row-I and all are facing South while P, Q, R, S and T are seated in row-II and all are facing North. There is a vacant seat in each row. The distance between any two adjacent seats is same so that each seat in row I is exactly opposite one seat in row II. K sits third to the right of the person who sits opposite to the immediate neighbour of R. Only one person sits between K and M as well as T and Q. Neither T nor Q sits adjacent to R and the vacant seats are not opposite to each other and they are not at extremes. L sits opposite P and he is not an immediate neighbour of K or M. S does not face J. Immediate neighbour of J face Q. M does not face Q.
6. Who sits opposite K?
1) T 2) Q 3) S 4) R 5) P
7. How many persons sit between J and M?
1)Five 2) Four 3) Three 4) Two 5) None
8. Four of the following five are alike in a certain way hence form a group. Find the one which does not belong to that group?
1) M 2) T 3) S 4) L 5) P
9.What is the position of R with respect to the one who sits opposite N?
1) Third to the right 2) Third to the left 3) immediate right 4) Immediate left 5) None of these
10.Which of the given statements is definitely true according to the given information?
1) P sits second to the right of Q 2) J sits adjacent to vacant seat 3) S and R are immediate neighbours of the vacant seat 4) J sits opposite to N
5) C and N sit adjacent to each other
Solutions for questions 6 to 10:
It is given that K sits third to the right of the person who sits opposite the immediate neighbour of R. Only one person sits between K and M as well as T and Q. Neither T nor Q sits adjacent to R. Hence R sits at the right end or at the second place from the right end of the row-II and K sits at the right end or at the third seat from the right end of the row. It can be shown as follows.
L sits opposite P but he does not sit adjacent to K or M. Hence it is not possible in case (i). Hence it is eliminated. In case (ii), P sits to the immediate right of R at the extreme right end and faces L. In case (iii), P and L sit at either ends depending upon M. As only one person sits between Q and T and neither Q nor T sits adjacent to R. The possible arrangements are as follows.
But vacant seats are not opposite each other and they are not at any extreme end. S does not face J. M does not face Q. Hence the final arrangement is as follows.
6. Q sits opposite to K. Choice (2)
7. Two persons sit between J and M. Choice (4)
8. Except S all sits at the ends. Choice (3)
9. S sits opposite N and R sits third to the right of S. Choice (1)
10. J sits adjacent to vacant seat is true. Choice (2)
(vii) Single row with distribution:
Directions (11-15): These questions are based on the following information.
Eight people viz. K, L, M, N, W, X, Y and Z are sitting in a straight line. They all are facing north. Each one of them has a different age i.e. 14, 16, 17, 19, 21, 23, 26 and 31 year, but not necessarily in the same order. L sits at one of the extreme end of the row. There are three persons sitting between M and X. X is of neither 14 nor 19 years old. There are two persons sitting between N and the person whose age is 23 years. Neither X nor N is the oldest person. Age difference of immediate neighbours of N is 5years. K sits right to the Y, but not immediate right. There are three persons sitting between L and one whose age is 16 years. The one whose age is 19 years sits third to the right of M. Y sits to the right of L. X sits second to the right of the person whose age is 23 years. W sits to the immediate left of the person whose age is 14 years. The one, whose age is 31 years is not immediate neighbour of the youngest person, M is not the fourth oldest person.
11. Who sits second to the right of N?
1) K 2) Z 3) W 4) Y 5) L
12. How many persons sit between the person whose age is 31 years and Z?
1) Four 2) Five 3) Three 4) One 5) Six
13. Who among the following person is 26 years old?
1) Y 2) N 3) M 4) Z 5) K
14. If W is related to 16 years in the same way as L is related to 26years, then which of the following is Y related to, following the same pattern?
1) 19 years 2) 17 years 3) 21 years 4) 31 years 5) 14 years
15. What is the age difference of K’s immediate neighbours?
1) Four 2) Six 3) Three 4) One 5) Five
Solutions for questions 11 to 15:
It is given that L sits at one of the extreme ends of the row. Hence L sits at either left end or right end but Y sits to the right of L. Hence L sits at the left end of the row and three people sit between L and the one whose age is 16 years. Hence the one whose age is 16 years sits fourth to the right of L. It is also given that three persons sit between M and X and the one whose age is 19 years old sits third to the right of M and X sits second to the right of 23 years old. The only possibility for M and X is X sits at the right end of the row and M sits third to the right of L. The one whose age is 19 years old and the one whose age is 23 years old sit accordingly. It can be shown as follows.
Only two persons sit between N and the one whose age is 23 years old, hence N sits to the immediate left of M. W sits to the immediate left of the one whose age is 14 years. X is neither 14 years nor 19 years old. Hence N’s age is 14 years and W sits to the immediate left of N. Age difference between the immediate neighbours of N is 5 years but the one whose age is 31 years is not an immediate neighbour of the youngest person. Hence the ages of immediate neighbours is 21 years in any order. It can be shown as follows.
M is not the fourth oldest person. Hence M’s age is 26 years and W’s age is 21 years. X is not the oldest person hence L’s age is 31 years and X’s age is 17 years. K sits to the right of Y but not immediate right. Hence K sits to the immediate left of X and Y sits to the immediate right of M and their ages are 19 years and 16 years respectively. Z sits between Y and K and his age is 23 years old. The final seating arrangement is as follow.
11. Y sits second to the right of N. Choice (4)
12. Four persons sit between L whose age is 31 years and Z. Choice (1)
13. M is of 26 years old. Choice (3)
14. W sits third to the left of 26 years old and L sits third to the left of 26 years old in the same way Y sits third to the left of 17 years old. Choice (2)
15. K’s immediate neighbours are X and Z and their age difference is 23 – 17 = 6years.
Choice (2)
