Introduction
Ranking questions often ask for a person’s position from one side of a line - such as from the left or right end. This pattern is fundamental because it forms the base for all advanced ranking and order questions.
Mastering this concept helps you quickly switch between left and right positions in seconds.
Pattern: Simple Position from One End
Pattern
The key idea: Total + 1 = Left position + Right position.
To find the position from the opposite end:
Right position = Total - Left position + 1
Step-by-Step Example
Question
In a row of 20 students, Rohan is 7th from the left end. What is his position from the right end?
Solution
-
Step 1: Identify the total number of students
Total = 20 -
Step 2: Note the given position from one end
Rohan’s position from the left = 7th -
Step 3: Apply the formula
Right position = 20 - 7 + 1 = 14 -
Final Answer:
14th from the right -
Quick Check:
Left (7) + Right (14) = 21 → which is Total (20) + 1 ✅
Quick Variations
1. Given position from right, find position from left.
2. Given total and one side rank, find the opposite side rank.
3. Sometimes the total is unknown - use the same formula to find total.
Trick to Always Use
- Step 1 → Add both side positions; subtract 1 to get total.
- Step 2 → Subtract known position from total and add 1 to get opposite position.
Summary
Summary
- The sum of left and right positions is always total + 1.
- To find the opposite side, use: Right = Total - Left + 1.
- Same applies for Left = Total - Right + 1.
- Always cross-check using the total + 1 rule.
Example to remember:
In a row of 25 students, 10th from left = 16th from right ✅ (since 10 + 16 = 26 = 25 + 1)
Hint: Right position = Total - Left + 1
Common Mistakes: Forgetting to add +1 after subtraction.