This Bankers Tutorial article is independent educational material. Examples are illustrative, and changing rules or examination requirements should be checked at the official source.
01 / UNDERSTANDING
Understand the idea
Numbered slots expose off-by-one errors quickly. They show whether the endpoints are included in the count and why a person counted from both ends must be counted only once.
02 / UNDERSTANDING
The concept in context
For one person ranked from both ends of a single ordered list, total count equals the two ranks added together minus one. The subtraction avoids counting that person twice. Questions involving two different people need an additional relation or overlap analysis; the one-person formula cannot be applied blindly.
The number between two known positions in the same direction is their difference minus one. Ties and shared ranks require explicit handling if permitted by the problem. Draw numbered slots when uncertain, especially when phrases such as ahead of, from the bottom and between appear in the same narrative.
03 / UNDERSTANDING
A worked learning case
Original educational case. An original queue places Leela seventh from the front and ninth from the back. The total is 7 + 9 − 1 = 15. If another person stands fourth from the front, there are two people between that person and Leela, occupying fifth and sixth positions. The two questions use related but different subtraction steps.
ORIGINAL EDUCATIONAL PRACTICE
Try it before you check.
Original practice: A person is 12th from the top and 18th from the bottom, with no ties. How many people are in the list?
Show the answer and reasoning
29 people.
Add the two inclusive ranks and subtract the person counted in both: 12 + 18 − 1 = 29. A quick diagram places eleven people above and seventeen below, plus the person, also giving 29. The formula depends on both ranks describing the same person in the same untied list.
Two traps to watch for.
- Forgetting that the focal person appears in both ranks.
- Using the one-person total formula for two unrelated people.
YOUR TOPIC-SPECIFIC LEARNING MAP
Turn understanding into practice
State whether ranks refer to one person.
Draw the two inclusive counts.
Check between-counts using numbered positions.
Explain the idea, apply it to a new situation, then check what changed in your reasoning.
BANKERS TUTORIAL · SOURCE NOTES
Keep the source alongside your notes.
Official links provide subject context and authoritative reference material. This guide’s explanation, scenario and question are original Bankers Tutorial learning content.
- sbi.bank.in https://sbi.bank.in/web/careers/current-openings
- sbi.bank.in https://sbi.bank.in/webfiles/uploads/files_2627/09/SBI_JA-Customer_Support_Sales-IH_Pre-2026-27_Eng.pdf
For SBI preparation, check the current official notice before relying on changing dates, rules or examination requirements.
