📑 Topics on this page (Jump to Topic):
📌 1. Key Formulas
| Situation | Formula |
|---|---|
| One person's rank from both ends | Total = L + R − 1 |
| Rank from right | R = Total − L + 1 |
| Between two persons (no overlap) | Total − (A + B) |
| Overlap (A + B > Total) | (A + B) − Total − 2 |
| Interchange | Use new rank: Total = (A's new rank) + (A's rank from the other end) − 1 |
⚠️ Exam Traps:
- For 'minimum number of persons', also check the overlap case.
- If 7th from top and 7th from bottom is the same person, total = 13, not 14.
📌 2. Comparison-based Ordering
- Write each statement as symbols: A > B, C < A …
- Arrange on one line from largest to smallest.
- If a place is not fixed, choose 'cannot be determined'.
💡 Memory Tip: In comparison questions, find the tallest/shortest first — the rest fall into place.
📌 3. Practice MCQs
📝 Practice MCQs (prepared by SF Prep — not PYQs)
Q1. In a row Ram is 12th from the left and 9th from the right. How many persons are in the row? Practice
Correct answer: (B)
Total = 12 + 9 − 1 = 20.
Total = 12 + 9 − 1 = 20.
Q2. In a class of 40, Mohan is 15th from the top. What is his rank from the bottom? Practice
Correct answer: (C)
40 − 15 + 1 = 26.
40 − 15 + 1 = 26.
Q3. In a row of 30, A is 10th from the left and B is 12th from the right. How many people are between A and B? Practice
Correct answer: (D)
30 − (10 + 12) = 8.
30 − (10 + 12) = 8.
Q4. In a row of 25, P is 15th from the left and Q is 14th from the right. How many are between P and Q? Practice
Correct answer: (A)
Q is 25 − 14 + 1 = 12th from the left. P is 15th ⇒ 13th and 14th are between = 2.
Q is 25 − 14 + 1 = 12th from the left. P is 15th ⇒ 13th and 14th are between = 2.
Q5. A is taller than B; C is taller than A; D is shorter than B. Who is the shortest? Practice
Correct answer: (B)
C > A > B > D, so D is the shortest.
C > A > B > D, so D is the shortest.
Q6. In a row A is 8th from the left and B is 10th from the right. After they interchange, A becomes 15th from the left. How many are in the row? Practice
Correct answer: (C)
A is now at B's old place: 15 from left, 10 from right ⇒ 15 + 10 − 1 = 24.
A is now at B's old place: 15 from left, 10 from right ⇒ 15 + 10 − 1 = 24.
Q7. Reena is 7th from the top and 28th from the bottom. How many students are in the class? Practice
Correct answer: (D)
7 + 28 − 1 = 34.
7 + 28 − 1 = 34.
Q8. Among five friends, P is heavier than Q but lighter than R. S is heavier than P but lighter than R. T is the lightest. Who is the third heaviest? Practice
Correct answer: (A)
R > S > P > Q > T; third heaviest is P.
R > S > P > Q > T; third heaviest is P.
Q9. In a row of boys, Sunil is 14th from the left and also 14th from the right. How many boys? Practice
Correct answer: (B)
14 + 14 − 1 = 27.
14 + 14 − 1 = 27.
Q10. In a queue of 50, X is 20th from the front. How many students are between X and the 10th from the back? Practice
Correct answer: (C)
10th from back = 41st from front. Between: 41 − 20 − 1 = 20.
10th from back = 41st from front. Between: 41 − 20 − 1 = 20.
Q11. A is 10th from the left, B is 10th from the right, and 4 persons sit between them (A to B's left). Minimum number of persons? Practice
Correct answer: (D)
A(10) + 4 between + B = 15th from left; B is 10th from right ⇒ 15 + 10 − 1 = 24.
A(10) + 4 between + B = 15th from left; B is 10th from right ⇒ 15 + 10 − 1 = 24.
Q12. There are 45 students. Ramesh ranks 18th from the top. How many students rank below him? Practice
Correct answer: (A)
45 − 18 = 27 students are below him.
45 − 18 = 27 students are below him.
Q13. M is older than N; O is older than M; P is older than O. Who is the second youngest? Practice
Correct answer: (B)
P > O > M > N; second youngest is M.
P > O > M > N; second youngest is M.
Q14. There are 60 people in a row. How many are between the 22nd from the left and the 22nd from the right? Practice
Correct answer: (C)
22nd from right = 39th from left. Between: 39 − 22 − 1 = 16.
22nd from right = 39th from left. Between: 39 − 22 − 1 = 16.
Q15. Rahul is 18th from the left. If he moves 5 places to the right, he becomes 12th from the right. How many are in the row? Practice
Correct answer: (D)
New rank 23rd from left; 23 + 12 − 1 = 34.
New rank 23rd from left; 23 + 12 − 1 = 34.
Q16. P scored more than Q; R scored more than P but less than S. Who scored the highest? Practice
Correct answer: (A)
S > R > P > Q.
S > R > P > Q.
Q17. A person 9th in a queue is 21st from the back. How many people are in the queue? Practice
Correct answer: (B)
9 + 21 − 1 = 29.
9 + 21 − 1 = 29.
Q18. In a row of 20, A is 15th from the left and B is 12th from the right. How many are between A and B? Practice
Correct answer: (C)
B is 20 − 12 + 1 = 9th from left; between = 15 − 9 − 1 = 5. (Formula: 15 + 12 − 20 − 2 = 5)
B is 20 − 12 + 1 = 9th from left; between = 15 − 9 − 1 = 5. (Formula: 15 + 12 − 20 − 2 = 5)
Q19. A is younger than B and C. D is younger than C but older than A. B is not the oldest. Who is the oldest? Practice
Correct answer: (D)
A is youngest, D < C, B is not oldest ⇒ C is the oldest.
A is youngest, D < C, B is not oldest ⇒ C is the oldest.
Q20. There are 35 girls in a row. Soni is 16th from the left. What is her position from the right? Practice
Correct answer: (A)
35 − 16 + 1 = 20.
35 − 16 + 1 = 20.