SBI Clerk – Quantitative Aptitude
Topic: Caselets
Caselets are interview‑style questions that give you a short “case” (a paragraph of facts) and ask you to answer a question based on that case.
They appear frequently in the SBI Clerk exam (and many other competitive exams) because they test your ability to read, analyse, and solve problems under time pressure.
1. Simple Explanation
A caselet looks like a mini‑story containing facts, numbers, and a final question.
Your job:
- Read the whole case carefully – the answer is usually hidden in the details.
- Identify the key data – numbers, relationships, and constraints.
- Eliminate options that contradict the facts or violate constraints.
- Calculate/derive the answer (or the most plausible one) using quick arithmetic or logic.
- Select the correct option from the given choices.
Tip: Treat a caselet as a mini‑questionnaire – all the information you need is in the paragraph.
2. Key Points & Strategies
| Strategy | Why It Helps | How to Apply |
|---|---|---|
| Read once, then re‑read | First pass gets the gist; second pass catches details you might miss. | Read the case fully, then skim for numbers & relationships. |
| Highlight / underline | Quickly spot important figures and constraints. | Use a pencil or a digital tool to underline numbers and key words (e.g., “greater than”, “exactly”, “in total”). |
| Create a mini‑table | Organises data for quick reference. | List entities (people, items, dates) in rows and attributes in columns. |
| Elimination first | Reduces the answer space dramatically. | Mark options that are impossible (e.g., a number that is too high). |
| Check units & consistency | Prevents plugging in wrong numbers. | Verify that all numbers use the same units (days vs. months, rupees vs. dollars). |
| Use “What if” scenarios | Helps confirm the chosen answer. | Assume the answer is true and see if any contradictions arise. |
| Avoid over‑thinking | Saves time. | Stick to the facts; if a step seems unnecessary, skip it. |
3. Common Types of Caselets in SBI Clerk
| Category | Typical Question Types | Key Skill |
|---|---|---|
| Arithmetic / Percentages | “If 20% of the students passed, how many students passed?” | Basic percentage calculations |
| Ratios & Proportions | “The ratio of boys to girls is 3:4. If there are 21 boys, how many girls?” | Ratio manipulation |
| Time & Speed | “A train travels 120 km in 2 hrs. How long will it take to travel 300 km?” | Speed = Distance ÷ Time |
| Work & Time | “A can finish a job in 8 days, B in 12 days. How long together?” | Work‑rate formula |
| Profit & Loss | “A shop sold 100 items at ₹200 each, incurring a 10% loss.” | Profit/Loss calculations |
| Simple Algebra | “If x + y = 10 and x – y = 4, find x.” | Basic algebraic manipulation |
| Combinatorics | “How many ways can 3 persons be seated in 5 seats?” | Permutations / combinations |
| Word Problems | “A recipe calls for 200 g of flour. If you want 3/4 of the recipe, how much flour?” | Proportion & scaling |
4. Worked Example
Caselet
Case
There are 12 students in a class.
7 of them are boys.
The sum of the ages of all the boys is 140 years.
The average age of the girls is 16 years.Question
What is the total number of years of all the girls in the class?
Step‑by‑Step Solution
| Step | What to Do | Explanation |
|---|---|---|
| 1. Extract key data | - Total students = 12 - Boys = 7 - Sum of boys’ ages = 140 - Avg. age of girls = 16 |
All numbers are given. |
| 2. Find number of girls | Girls = Total – Boys = 12 – 7 = 5 | Simple subtraction. |
| 3. Compute total age of girls | Total age = Average × Number = 16 × 5 = 80 | Multiplication of average by count. |
| 4. Verify | Nothing else needed; the answer must be one of the options. | Ensure no contradictions. |
| Result | 80 years | The total age of all girls is 80 years. |
Answer: 80 years (Option C if options were A=60, B=70, C=80, D=90).
5. Quick Revision Summary
- Read the entire case before solving.
- Highlight all numbers and constraints.
- Build a mini‑table if multiple entities are involved.
- Eliminate impossible options first.
- Use basic formulas (percentage, ratio, speed, work, profit/loss, algebra).
- Check for consistency (units, total counts).
- Verify by a quick “what if” sanity check.