SSC CHSL Maths Questions: Numerical Ability Examples

SSC CHSL Maths Questions are important for students who want to clear written exams with good marks. In SSC CHSL, maths is not only about knowing formulas. It is about understanding the question quickly, choosing the right method, and avoiding small calculation mistakes. Many students lose marks because they read the question in a hurry or because they try long school methods where a small shortcut can save time.

This page explains the important maths topics for SSC CHSL in simple language. The aim is to help students preparing for LDC, DEO and 10+2 level government posts revise formulas, understand common question types, and practice exam-style solved examples. The questions given here are not claimed as exact official previous-year questions. They are written in the same style as questions commonly seen in government job written exams, railway exams, banking exams, police exams and other aptitude tests.

The paper usually checks class 10 level arithmetic, basic algebra, geometry and fast calculation. Because of this, your preparation should have two parts. First, learn the basic formula and concept. Second, solve many examples until you can identify the type of question immediately. A beginner should not jump directly to difficult mock tests. Start with topic-wise practice, then move to mixed practice.

Important maths topics for SSC CHSL

The following topics are useful for SSC CHSL maths preparation. Some exams ask all topics directly, while some exams mix two topics in one question. For example, a profit and loss question may also include percentage. A time and work question may also include ratio. That is why the basic chapters should be revised together.

Simplification
Fractions
Percentage
Average
Ratio
Profit and Loss
Discount
Simple Interest
Time and Work
Speed and Distance
Geometry
Data Interpretation

How to prepare maths for SSC CHSL

Start from number system, simplification, percentage, ratio and average. These chapters are the base of many other topics. After this, study profit and loss, discount, interest, time and work, time and distance, mensuration and data interpretation. When your basics become clear, solve mixed questions daily. In written exams, the same formula may be asked in many different forms.

Make a small formula notebook. Do not write only formulas; write one solved example below each formula. This helps you remember where the formula is used. For speed, learn tables up to 20, squares up to 30, cubes up to 15, fraction to percentage conversion and common multiplication tricks. These small things reduce pressure in the exam hall.

Basic formulas to remember

Average = sum of observations / number of observations.
Percentage = value / total value × 100.
Profit = selling price – cost price.
Loss = cost price – selling price.
Profit percent = profit / cost price × 100.
Simple Interest = principal × rate × time / 100.
Speed = distance / time.
Work done in one day = 1 / total days.
Area of rectangle = length × breadth.
Area of triangle = 1/2 × base × height.
Volume of cuboid = length × breadth × height.
LCM × HCF = product of two numbers.

Solved SSC CHSL maths examples

The examples below are written in the pattern of written job exams. Read each question carefully, then see the method. Try to solve the same question again without looking at the solution.

Example 1: Simplification

Question: Simplify 48 ÷ 6 + 7 × 3 – 5.

Solution: First divide and multiply: 48 ÷ 6 = 8 and 7 × 3 = 21. Now 8 + 21 – 5 = 24. Answer: 24.

Example 2: Percentage

Question: A candidate scores 72 marks out of 80. Find the percentage.

Solution: Percentage = obtained marks / total marks × 100 = 72 / 80 × 100 = 90%. Answer: 90%.

Example 3: Average

Question: The average of 12, 15, 18, 20 and 25 is what?

Solution: Sum = 90 and number of values = 5. Average = 90 / 5 = 18. Answer: 18.

Example 4: Ratio

Question: Divide Rs 960 in the ratio 5:7.

Solution: Total parts = 12. One part = 960 / 12 = 80. Shares are 5 × 80 = 400 and 7 × 80 = 560. Answer: Rs 400 and Rs 560.

Example 5: Profit and Loss

Question: A book is bought for Rs 250 and sold for Rs 300. Find profit percent.

Solution: Profit = 50. Profit percent = 50 / 250 × 100 = 20%. Answer: 20%.

Example 6: Discount

Question: Marked price is Rs 800 and discount is 15%. Find selling price.

Solution: Discount = 15% of 800 = 120. Selling price = 800 – 120 = 680. Answer: Rs 680.

Example 7: Simple Interest

Question: Find simple interest on Rs 5000 at 8% per year for 2 years.

Solution: SI = PRT / 100 = 5000 × 8 × 2 / 100 = 800. Answer: Rs 800.

Example 8: Compound Interest

Question: Find compound amount on Rs 1000 at 10% for 2 years.

Solution: Amount = 1000 × 1.1 × 1.1 = 1210. CI = 210. Answer: amount Rs 1210.

Example 9: Time and Work

Question: A can finish work in 12 days and B in 18 days. Find one day work together.

Solution: A’s one day work = 1/12 and B’s = 1/18. Together = 5/36. Time = 36/5 = 7.2 days.

Example 10: Time and Distance

Question: A train travels 180 km in 3 hours. Find speed.

Solution: Speed = distance / time = 180 / 3 = 60 km/h. Answer: 60 km/h.

Example 11: Mensuration

Question: Find area of a rectangle of length 18 cm and breadth 11 cm.

Solution: Area = length × breadth = 18 × 11 = 198 square cm. Answer: 198 square cm.

Example 12: Algebra

Question: If 3x + 5 = 26, find x.

Solution: 3x = 21, so x = 7. Answer: 7.

Example 13: Data Interpretation

Question: A table shows sales 120, 150, 180. Find average sale.

Solution: Average = (120 + 150 + 180) / 3 = 450 / 3 = 150. Answer: 150.

Example 14: Fractions

Question: Find 3/5 of 250.

Solution: 3/5 of 250 = 150. Answer: 150.

Example 15: LCM and HCF

Question: Find HCF of 24 and 36.

Solution: Factors common at highest value give 12. Answer: 12.

Example 16: Number System

Question: Which is divisible by 9: 4374 or 5321?

Solution: Sum of digits of 4374 is 18, divisible by 9. Sum of 5321 is 11. Answer: 4374.

Example 17: Boats and Streams

Question: A boat speed is 12 km/h in still water and stream is 3 km/h. Find downstream speed.

Solution: Downstream speed = 12 + 3 = 15 km/h. Answer: 15 km/h.

Example 18: Pipes and Cisterns

Question: A pipe fills a tank in 10 hours and another in 15 hours. Find time together.

Solution: One hour work = 1/10 + 1/15 = 1/6. Time = 6 hours. Answer: 6 hours.

Example 19: Ages

Question: A father is 4 times his son’s age. Sum of ages is 50. Find son’s age.

Solution: Let son = x, father = 4x. Then 5x = 50, x = 10. Answer: 10 years.

Example 20: Calendar

Question: If 1 January is Monday, what day is 8 January?

Solution: After 7 days the same day repeats. Answer: Monday.

Mixed practice questions with answers

These practice questions are useful for quick revision before a written exam. First solve them yourself, then check the answer. If your answer is wrong, do not only see the final answer. Find whether the mistake was in formula, calculation, unit conversion or question reading.

A man spends 75% of his salary and saves Rs 4500. Find his salary. Answer: Rs 18000.
The average of six numbers is 18. If one number 30 is removed, find the new average when the sum of remaining numbers is 78. Answer: 15.6.
A shopkeeper gives 20% discount on Rs 1200. Find selling price. Answer: Rs 960.
A sum becomes Rs 6600 in 2 years at 10% simple interest. Find principal. Answer: Rs 5500.
A person covers 240 km in 4 hours. Find speed. Answer: 60 km/h.
Two numbers are in ratio 3:5 and their sum is 96. Find the numbers. Answer: 36 and 60.
A can do work in 8 days and B can do it in 12 days. Find time together. Answer: 24/5 days.
Find the area of a square whose side is 17 cm. Answer: 289 square cm.
If x + 7 = 19, find x. Answer: 12.
Find 18% of 500. Answer: 90.
Find the HCF of 45 and 75. Answer: 15.
Find the LCM of 12 and 18. Answer: 36.
A train of 120 m crosses a pole in 6 seconds. Find speed in m/s. Answer: 20 m/s.
A candidate got 135 marks out of 180. Find percentage. Answer: 75%.
Cost price is Rs 900 and profit is 12%. Find selling price. Answer: Rs 1008.

Shortcut tricks for written exams

For percentage questions, use fraction values. 50% is 1/2, 25% is 1/4, 20% is 1/5, 12.5% is 1/8 and 10% is 1/10. This makes calculation faster. If the question says 25% of 640, think one-fourth of 640, which is 160. If it says 12.5% of 800, think one-eighth of 800, which is 100.

For average questions, use total sum. If average of 20 students is 45, total marks are 20 × 45 = 900. If one student is added or removed, update the total first, then divide again. Many exam questions become easy when you convert average into total.

For ratio questions, add the parts. If a quantity is divided in 4:5:6, total parts are 15. One part is total quantity divided by 15. This method works in income, expenditure, age, partnership and mixture questions.

For time and work questions, use one-day work. If a person completes work in 10 days, one-day work is 1/10. If another completes it in 15 days, one-day work is 1/15. Add the work rates to get combined work. This avoids confusion.

For speed questions, keep units same. If distance is in kilometre and time is in hour, speed is km/h. If length of train is in metre and time is in seconds, speed is m/s. To convert m/s to km/h, multiply by 18/5. To convert km/h to m/s, multiply by 5/18.

Common mistakes in SSC CHSL maths

Using selling price instead of cost price while calculating profit percent.
Forgetting to convert mixed fractions into improper fractions.
Applying discount on cost price when the question gives marked price.
Mixing kilometre per hour and metre per second in train questions.
Reading percentage increase as percentage decrease. These are not always equal.
Writing only final answer without checking whether the question asks ratio, percent, amount or difference.
Spending too much time on one question and losing easier questions later.

Practice set for SSC CHSL

Find 35% of 420. Answer: 147.
A number is 30% less than 500. Find the number. Answer: 350.
Find average of 11, 13, 15, 17 and 19. Answer: 15.
Divide 750 in the ratio 2:3. Answer: 300 and 450.
Find profit percent if CP is Rs 600 and SP is Rs 690. Answer: 15%.
Find loss percent if CP is Rs 800 and SP is Rs 720. Answer: 10%.
Find SI on Rs 2400 at 5% for 3 years. Answer: Rs 360.
A car travels 150 km in 2.5 hours. Find speed. Answer: 60 km/h.
A and B together complete work in 6 days. Their one-day work is what? Answer: 1/6.
Find area of triangle with base 20 cm and height 12 cm. Answer: 120 square cm.
Find 7/8 of 320. Answer: 280.
Find the square of 23. Answer: 529.
Simplify 18 + 6 × 4 – 12 ÷ 3. Answer: 38.
A value changes from 80 to 100. Find percentage increase. Answer: 25%.
Find the next number: 5, 10, 20, 40, ?. Answer: 80.

FAQ on SSC CHSL Maths Questions

Which maths topics are most important for SSC CHSL?

Percentage, ratio, average, profit and loss, interest, time and work, speed and distance, simplification, number system and data interpretation are very important. For higher level exams, algebra, geometry and mensuration also become important.

How many questions should I practice daily?

A beginner can start with 25 questions daily. After one or two weeks, increase it to 50 questions. Before the exam, solve mixed sets with a timer so that speed and accuracy improve together.

Should I learn shortcuts first?

First understand the basic method. After that learn shortcuts. If you learn only shortcuts without concept, you may get confused when the question is slightly changed.

Are these exact previous-year questions?

No. These are exam-style practice questions based on common patterns seen in written job exams. They are meant for learning and revision.

Conclusion

SSC CHSL Maths Questions become easier when you study formulas with examples and practice mixed questions regularly. Focus on accuracy first, then slowly improve speed with daily timed practice.

Extra practice example

Question: A man walks at 5 km/h. How much distance will he cover in 2.5 hours?

Method: Distance = speed × time = 5 × 2.5 = 12.5 km. Answer: 12.5 km. This type of question is useful because it checks formula selection and simple calculation. In the exam, read the unit, identify the given values, write the formula mentally and then calculate step by step.

Extra practice example

Question: If 15 workers finish a work in 12 days, how many worker-days are required?

Method: Worker-days = 15 × 12 = 180. Answer: 180 worker-days. This type of question is useful because it checks formula selection and simple calculation. In the exam, read the unit, identify the given values, write the formula mentally and then calculate step by step.