Preparing for SSC GD 2026 requires a strong command of Mathematics, as it plays a key role in boosting your overall score. The SSC GD 2026 Maths Top 501 Most Important Questions are carefully selected to cover all high-weightage topics like Arithmetic, Algebra, Geometry, and Mensuration.
Practising these questions helps candidates improve speed, accuracy, and confidence while understanding the exam pattern and frequently asked concepts.
To solve the Top 501 Most Important Questions, first understand the approach and shortcuts from the video. For additional practice and clarity on key concepts, refer to the questions and explanations provided below.
The Mathematics section of the SSC GD exam features 20 questions, with each question carrying 2 marks. There is negative marking. Mathematics is often a deciding factor for selection, as many applicants struggle here. A strong score in this section can determine rank and help secure preferred jobs. Due to negative marking, avoid random guesses.
Average: At least one, often two questions.
Profit & Loss and Discount: Combined, these account for three questions.
Time & Work
Time, Speed & Distance
Mensuration
Compound Interest (CI) & Simple Interest (SI)
Percentage
Ratio & Proportions
These topics, though lower in weightage, often provide easy, guaranteed marks.
Number System: One question, consistently repeated.
HCF & LCM: One question, consistently asked.
Simplification: If BODMAS rule is known, one question is guaranteed.
Power & Indices: Sometimes appears if Simplification is not present.
Pipe & Cistern
Boat & Stream
Statistics & Data Interpretation (DI): (Mean, Mode, Median) Occasionally asked.
Candidates can refer to the most important topics with few examples provided below for your reference.
Discount is a small topic that guarantees one free mark.
Discount is calculated on the Marked Price (MP), also known as the Maximum Retail Price (MRP).
Definition: Discount is the difference between the Marked Price and the Selling Price (SP).
Formula: Discount = Marked Price – Selling Price
Formula: Discount % = (Discount / Marked Price) * 100
Key Principle: Discount percentage is always calculated on the Marked Price.
Problem: An item has a Marked Price of ₹650 and is sold for ₹572. What is the discount percentage?
Solution:
Discount Amount = ₹650 – ₹572 = ₹78
Discount % = (₹78 / ₹650) * 100 = 12%
This is a very important relationship.
Formula: Selling Price (SP) = Marked Price (MP) * [(100 - Discount %) / 100]
Explanation: If an article has a 20% discount, its selling price is 80% of its marked price (100-20 = 80).
Problem: An item is sold with a 14% discount for ₹387. Find its Marked Price.
Solution:
SP = MP * [(100 - Discount %) / 100]
387 = MP * [(100 - 14) / 100] => 387 = MP * (86 / 100)
MP = (387 * 100) / 86 = ₹450
(Memory Tip: When faced with calculations, consider using unit digits or digital sums for option elimination if applicable, especially when time is limited.)
Problem: Find the selling price of an item with a Marked Price of ₹8980 after a 19% discount, to the nearest rupee.
Solution:
SP = MP * [(100 - Discount %) / 100]
SP = 8980 * [(100 - 19) / 100] = 8980 * (81 / 100)
SP = 89.80 * 81 = 7273.8
To the nearest rupee, SP = ₹7274.
Problem: A retailer offers a 10% discount on purchases between ₹1000 and ₹5000, and a 20% discount on purchases above ₹5000. If a customer buys goods worth ₹6000, what is their saving compared to the original price?
Solution:
The purchase of ₹6000 falls under the "above ₹5000" category, so a 20% discount applies.
Savings = 20% of ₹6000 = (20 / 100) * 6000 = ₹1200.
(Memory Tip: For such problems in an exam, quickly identify the applicable condition to save time. The length of the problem description does not always imply complexity.)
Concept 1 (Discount Amount): Discount = Marked Price – Selling Price
Concept 2 (Discount Percentage): Discount % = (Discount / Marked Price) * 100
Concept 3 (SP, MP, Discount % Relation): SP = MP * [(100 - Discount %) / 100]
If two successive discounts are x% and y%, the effective or net discount is given by:
Net Discount % = x + y - (xy / 100)
(Memory Tip: This formula and concept are highly likely to appear in the exam.)
The ratio method is useful for three or more successive discounts.
Convert Percentage to Fraction: P% = P/100. (e.g., 20% = 1/5 means 1 unit discount on 5 units MP).
Build Ratios (MP : SP): For a 1/5 discount, MP : SP = 5 : (5-1) = 5 : 4.
Multiply Ratios: For multiple discounts, multiply the MP values together and the SP values together. Cross-cancellation can simplify.
Problem: What is the effective discount for two successive discounts of 20% and 25%?
Solution:
Method 1: Formula Method
Net Discount % = 20 + 25 - (20 * 25 / 100) = 45 - 5 = 40%.
Method 2: Ratio Method
20% = 1/5 (MP:SP = 5:4)
25% = 1/4 (MP:SP = 4:3)
Multiply ratios: (5:4) * (4:3) = 5:3 (after cancelling 4).
Net Discount = (5-3)/5 * 100 = (2/5) * 100 = 40%.
For three or more successive discounts, the ratio method is generally more efficient.
(Memory Tip: Choose the ratio method when dealing with three or more successive discounts or when the fractions are straightforward. Choose the successive formula when dealing with two discounts or when fractions are complicated.)
This applies to promotions like "Buy 2, Get 1 Free".
Formula: Discount % = (Number of Free Articles / Total Number of Articles) * 100
Example: "Buy 3 shirts, Get 2 shirts Free"
Discount % = (2 / (3 + 2)) * 100 = (2 / 5) * 100 = 40%.
This concept establishes a direct relationship between Market Price (MP) and Cost Price (CP).
Formula: MP / CP = (100 + Profit %) / (100 - Discount %)
(Use -Loss % if there is a loss instead of profit).
Example Problem: An item is marked such that after a 20% discount, there is a 25% profit. How much above the cost price was it marked?
Solution:
MP / CP = (100 + 25) / (100 - 20) = 125 / 80 = 25 / 16.
If CP is 16 units, MP is 25 units. Increase = 25 - 16 = 9 units.
Percentage increase = (9 / 16) * 100 = 56.25%.
LCM stands for Least Common Multiple. It is the smallest positive integer that is a multiple of two or more given integers.
Example: LCM of 12 and 36 is 36. (36 is the smallest number divisible by both 12 and 36).
LCM Calculation (Prime Factorization Method): Divide numbers by prime factors until all are 1. Product of factors is LCM.
Fundamental LCM Property: If K is the LCM of numbers a, b, and c, then K will always be divisible by a, b, and c.
Rule 1: Last Digit Divisibility: If any number has a last digit of zero, then their LCM must also end in zero.
Rule 2: Digital Sum Divisibility: If the LCM must be divisible by a number like 9 (e.g., from 36 or 45), its digital sum must be divisible by 9.
Fundamental Formula: For any two positive integers (First Number and Second Number), their product is always equal to the product of their LCM and HCF.
First Number × Second Number = LCM × HCF
Problem: Given: LCM = 144, HCF = 8, First Number = 16. Find Second Number.
Solution: 16 × Second Number = 144 × 8 => Second Number = (144 × 8) / 16 = 72.
Problem: Sum of two numbers (a + b) = 15. HCF = 3, LCM = 18. Find the sum of their reciprocals (1/a + 1/b).
Solution:
Sum of reciprocals = (a + b) / (ab)
We know ab = LCM × HCF.
So, Sum of reciprocals = (a + b) / (LCM × HCF) = 15 / (18 × 3) = 15 / 54 = **5 / 18**.
Definition: HCF is the largest number that divides two or more numbers exactly.
Method: Prime Factorization: Take the lowest power of each common prime factor.
Example: HCF of 42 (2×3×7), 60 (2²×3×5), 72 (2³×3²) is 2¹×3¹ = 6.
If K is the HCF of numbers a, b, and c, then K will always divide a, b, and c.
Option Elimination: Check which options divide all given numbers, then choose the largest.
For numbers expressed as products of prime powers (e.g., 2^a * 3^b * 5^c), for each common prime factor, take the lowest power.
Example: HCF of (2² × 3⁵ × 5³) and (2⁴ × 3² × 5¹) is 2² × 3² × 5¹.
Problem: Find the ratio of LCM to HCF for 42 and 49.
Solution:
HCF(42, 49) = 7
LCM(42, 49) = 294
Ratio = LCM : HCF = 294 : 7 = 42 : 1.
This is a very important topic.
If two numbers are in the ratio A : B (coprime), and their HCF is H, then:
LCM = H × A × B
First Number = A × H
Second Number = B × H
(Memory Tip: Any number derived from or related to a given HCF will always be a multiple of that HCF. This is a powerful tool for option elimination.)
Problem: Two numbers are in the ratio 13 : 9. Their HCF = 13. Find the larger number.
Solution:
First Number = 13 × 13 = 169
Second Number = 9 × 13 = 117
The larger number is 169.
The relationship: LCM = HCF × a × b (where a:b is the ratio).
Problem: Ratio of two numbers = 3:5; LCM = 240. Find HCF and the two numbers.
Solution:
Calculate HCF: 240 = HCF × 3 × 5 => HCF = 240 / 15 = 16.
Numbers: 16 × 3 = 48 and 16 × 5 = 80.
Definition: A prime number is a natural number greater than 1 that has exactly two distinct positive divisors: 1 and itself (e.g., 2, 3, 5, 7).
Important Concept: If two numbers are prime, their LCM is their product.
Problem: Two prime numbers x and y (where x < y). Their LCM = 141. Find y - 5x.
Solution:
Since x and y are prime, their product is 141. Prime factorization of 141 = 3 × 47.
So, x = 3, y = 47.
y - 5x = 47 - (5 × 3) = 47 - 15 = 32.
If numbers are in ratio a:b:c… and their HCF is K, then numbers are a×K, b×K, c×K.
Problem: Three numbers in the ratio 4:3:7; HCF = 6. Find the sum of the three numbers.
Solution:
Method 1: Individual Numbers
Numbers: 4×6 = 24, 3×6 = 18, 7×6 = 42.
Sum: 24 + 18 + 42 = 84.
Method 2: Sum of Ratio Parts
Sum of ratio parts = 4 + 3 + 7 = 14.
Total sum = 14 × HCF = 14 × 6 = 84.
Problem: Find the HCF of 16³ and 48².
Solution:
16³ = 16 × 16 × 16
48² = (16 × 3) × (16 × 3) = 16 × 16 × 3 × 3
Highest common factors are 16 × 16.
HCF = 16 × 16 = 256.
To find the smallest number that leaves a specific remainder (R) when divided by several numbers (N1, N2, N3…):
Required number = LCM (N1, N2, N3…) + R
Problem: Find the smallest 4-digit number that leaves a remainder of 9 when divided by 10, 12, 15, 24, 30.
Solution:
LCM (10, 12, 15, 24, 30) = 120.
Smallest 4-digit multiple of 120: 1000 / 120 ≈ 8.33, so 9 × 120 = 1080.
Required number = 1080 + 9 = 1089.
(Memory Tip: When a problem asks for the maximum, greatest, or highest common quantity, calculate the HCF. When it asks for the minimum, least, or smallest, calculate the LCM.)
Problem: 16 cake pieces and 40 chocolates are to be distributed among children such that each child receives an equal number of both. Find the maximum number of children.
Solution: This is a "maximum distribution" problem, so calculate the HCF of 16 and 40.
HCF(16, 40) = 8. Maximum children = 8.
A fraction is a numerical representation a/b.
Rules for LCM and HCF of Fractions:
LCM of Fractions: LCM = (LCM of Numerators) / (HCF of Denominators)
HCF of Fractions: HCF = (HCF of Numerators) / (LCM of Denominators)
Problem: Find the LCM and HCF of the reciprocals of 18 and 24.
Solution: Reciprocals are 1/18 and 1/24.
LCM (1/18, 1/24) = LCM(1, 1) / HCF(18, 24) = 1 / 6 = 1/6.
HCF (1/18, 1/24) = HCF(1, 1) / LCM(18, 24) = 1 / 72 = 1/72.
Problem: Find the product of the LCM and HCF of the fractions: 4/5, 9/15, 3/25, 2/10, 2/3.
Solution:
LCM of Fractions: Numerators (4, 9, 3, 2, 2) => LCM = 36. Denominators (5, 15, 25, 10, 3) => HCF = 1.
LCM = 36/1 = 36.
HCF of Fractions: Numerators (4, 9, 3, 2, 2) => HCF = 1. Denominators (5, 15, 25, 10, 3) => LCM = 150.
HCF = 1/150.
Product (LCM × HCF) = 36 × (1/150) = 36/150 = 6/25.
(Note: Original lecture stated LCM as 252 for numerators (4,9,3,2,2) and simplified it from there. Recalculation shows LCM(4,9,3,2,2) = 36. Following the correct calculation: 36 * (1/150) = 6/25)
To calculate the LCM or HCF of decimal numbers, convert them into fractions with a common denominator (power of 10).
Problem: Find the HCF of 0.05, 0.5, 0.25, 1.25.
Solution:
Convert to fractions with denominator 100: 5/100, 50/100, 25/100, 125/100.
HCF = (HCF of Numerators (5, 50, 25, 125)) / (LCM of Denominators (100, 100, 100, 100))
HCF(5, 50, 25, 125) = 5. LCM(100, 100, 100, 100) = 100.
HCF = 5/100 = 0.05.
Problem: What is the minimum number of soldiers required to arrange them in rows of 12, 15, 16, and 18?
Solution: This requires finding the LCM of 12, 15, 16, 18.
LCM(12, 15, 16, 18) = 720.
When problems involve events occurring at different intervals and ask when they will occur together again, find the LCM of the individual intervals.
Problem: Four bells ring at intervals of 6, 8, 9, and 10 seconds. After how many minutes will they ring together again?
Solution:
LCM(6, 8, 9, 10) = 360 seconds.
Convert to minutes: 360 / 60 = 6 minutes.
The LCM of two or more numbers must always be a multiple of their HCF. Any number that is not a multiple of the HCF cannot be the LCM.
(Memory Tip: The LCM can never be a number that is not a multiple of the HCF.)
Problem: Two numbers are in the ratio 2:7. Their LCM is 42. Find the product of the two numbers.
Solution:
Let numbers be 2x and 7x. HCF = x. LCM = 14x.
Given LCM = 42, so 14x = 42 => x = 3.
Numbers are 2*3 = 6 and 7*3 = 21.
Product = 6 × 21 = 126.
Alternatively, using Product = LCM × HCF: 42 × 3 = 126.
Simple Interest is a type of interest calculation where the interest amount remains the same every year on the principal amount.
Principal (P): Initial amount invested/borrowed.
Rate of Interest (R): Percentage per annum.
Time (T): Duration, usually in years.
Simple Interest (SI): Interest earned/paid.
Amount (A): Total sum (Principal + SI).
SI = (P × R × T) / 100
(Memory Tip: To quickly calculate Simple Interest: Calculate the Simple Interest Percentage = R × T. Then, Simple Interest = Principal × (Simple Interest Percentage / 100).)
Problem: Find the simple interest on ₹2,00,000 at 7% for 2 years.
Solution:
SI Percentage = 7% × 2 = 14%.
SI = 14% of ₹2,00,000 = (14/100) * 2,00,000 = ₹28,000.
Amount = ₹2,00,000 + ₹28,000 = ₹2,28,000.
Multiply the rate (R) by the time (T).
Determine the simple interest percentage (R*T).
Multiply the principal amount by this percentage.
When time is in days, convert to years by dividing by 365.
(Memory Tip: 73 days = 1/5 year.)
Problem: Calculate SI for P = ₹48,750, R = 16%, T = 73 days.
Solution:
Time (T) = 73 / 365 = 1/5 year.
SI = (48750 * 16 * (1/5)) / 100 = (48750 * 16) / 500 = ₹1560.
To calculate days between two dates, count days in each month carefully.
Example: Feb 7, 2022 to April 20, 2022 (2022 is not a leap year).
Feb: (28 - 7) + 1 = 22 days.
Mar: 31 days.
Apr: 20 days.
Total = 22 + 31 + 20 = 73 days (1/5 year).
Problem: Calculate SI for P = ₹2,000, R = 8.25%, for Feb 7, 2022 to April 20, 2022.
Solution:
Time (T) = 73 days = 1/5 year.
SI = (2000 * 8.25 * (1/5)) / 100 = (2000 * 8.25) / 500 = ₹33.
Problem: A bike costs ₹60,000. Down payment = ₹10,000. Remaining amount at 15% SI for 2 years. Calculate SI to be paid.
Solution:
Remaining Principal (P) = ₹60,000 - ₹10,000 = ₹50,000.
Total SI Percentage = R * T = 15% * 2 = 30%.
SI = 30% of ₹50,000 = (30/100) * 50,000 = ₹15,000.