
GMAT Linear Equations questions are an important part of the GMAT Quant section. These questions check how well you understand algebra in real-life situations like comparing costs, finding ages, profits, differences, or determining unknown values.
You might get linear equation questions alone or as part of longer word problems. The good news is, they are easy to solve once you know the basic formulas and how to use them. Practice with the GMAT mock test and get familiar with the questions.
In this blog, you’ll find a simple formula PDF, a set of practice questions with answers, and a few extra problems to try on your own. You’ll also learn about common mistakes students make and easy tricks to save time during the exam.
You only need a few easy formulas to solve linear equation questions. These help you set up relationships between numbers and find unknown values correctly.
You can download the full formula PDF from the link above. Here’s a quick look at the main ones:
| Concept | Formula / Explanation |
|---|---|
| Basic Linear Equation | ax + b = c → x = (c − b) ÷ a |
| Two Variables (Simultaneous Equations) | Use Substitution or Elimination method to solve |
| Convert Ratios Into Variables | If ratio is A : B → Ax and Bx |
| Linear Relationship | Convert words like “more than” / “less than” into + or − |
| Ages in Equations | Present age ± number of years = future/past age |
| Cost / Profit Problems | Convert given relationships into linear expressions |
| Check the Answer | Always substitute result back into equation to verify |
These formulas are useful for solving questions about ages, cost-price and selling price, mixtures, and any situation with unknown values.
Students often make small but costly mistakes in linear equations. These mistakes usually happen due to rushing or forming wrong equations. A little extra attention can save a lot of marks.
Here are the most common ones to avoid:
Wrong variables or equation formation: Misreading statements like “more than” or “less than” changes the whole equation.
Sign errors (+ / – mistakes): A single minus mistake can lead to a completely wrong answer.
Not simplifying before solving: Reducing equations early saves time and avoids big numbers.
Ignoring real meaning in word problems: Understand relationships properly (like age or ratio) before solving.
Not checking the solution: Always substitute back to confirm the answer is correct.
Here’s a short set of GMAT-style linear equations questions to help you practice. They include all common types of age problems, ratio questions, part-whole, and two-step changes. Practice these often to get faster and more confident before your GMAT test.
A carrot, costing Rs. 30, has 50 units of Vitamin A and a beetroot, costing Rs. 40, has 60 units of Vitamin A. How should Ram spend Rs. 1200 to gain the maximum amount of Vitamin A?
correct answer:- 3
There are two positive numbers. The product of two-fifths of the first number and one-seventh of the second number equals 16 times the second number. Find the sum of the numbers.
correct answer:- 5
An airline has a certain free luggage allowance and charges for excess luggage at a fixed rate per kg. Two passengers, Raja and Praja, have 60 kg of luggage between them, and are charged Rs 1200 and Rs 2400 respectively for excess luggage. Had all of the luggage belonged to one of them, the excess luggage charge would have been Rs 5400. What is the weight of Praja’s luggage?
correct answer:- 4
An airline has a certain free luggage allowance and charges for excess luggage at a fixed rate per kg. Two passengers, Raja and Praja, have 60 kg of luggage between them, and are charged Rs 1200 and Rs 2400 respectively for excess luggage. Had all of the luggage belonged to one of them, the excess luggage charge would have been Rs 5400. What is the free luggage allowance?
correct answer:- 2
When you reverse the digits of the number 13, the number increases by 18. How many other two-digit numbers increase by 18 when their digits are reversed?
correct answer:- 2
Rita's present age is four times her daughter's present age and two-thirds of her mother's present age. The sum of all of their current ages is 154 years. What is the difference between Rita's and her mother's present age?
correct answer:- 1
In the following question, two equations are given.
I. $$2x^2+3x-20=0$$
II. $$2y^2+19y+44=0$$
Which of the following options is definitely true?
correct answer:- 4
In the following question, two equations are given.
I. $$10x^2-7x+1=0$$
II. $$35y^2-12y+1=0$$
Which of the following options is definitely true?
correct answer:- 4
If one-eighth of a number is 25.5, what is one-sixth of the same number?
correct answer:- 4
Which number should replace the question marks in the following equation?
$$\frac{?}{432}=\frac{243}{?}$$
correct answer:- 3
By how much is $$\frac{5}{12}$$ of 516 lesser than $$\frac{4}{9}$$ of 495 ?
correct answer:- 5
On Children's Day, sweets were to be equally distributed among 200 children. But on that particular day, 40 children remained absent; hence, each child got 2 sweets extra. How many sweets were distributed?
correct answer:- 4
The cost of 15 digital cameras and 21 handy cameras is Rs. 354900. What is the cost of 5 digital cameras and 7 handy cameras?
correct answer:- 2
A canteen requires 56 kg of rice for seven days. How many kilograms of rice will it require for the months of April and May together?
correct answer:- 4
While withdrawing an amount of Rs. 49,350/-, a customer mistakenly collects Rs. 48,150/-. The remaining amount is deposited back into his account by the bank, which shows the balance of Rs. 25,376/-. What will the customer’s balance be after depositing the remaining amount?
correct answer:- 1
The cost of 18 shirts and 21 pants is Rs. 42. What is the cost of 90 shirts and 105 pants?
correct answer:- 4
The cost of 15 pens and 20 pencils is Rs. 200. What is the cost of 180 pens and 240 pencils?
correct answer:- 3
The cost of 12 belts and 30 wallets is Rs 8,940. What is the cost of 4 belts and 10 wallets?
correct answer:- 2
The present ages of Ravi and Vishal are in the ratio 5:4. Ten years from today, their ages will be in the ratio of 6:5. What is Ravi’s present age?
correct answer:- 3
The cost of 10 calculators and 12 watches is Rs 11,100. What is the cost of 30 calculators and 36 watches?
correct answer:- 2
The cost of 24 bats and 32 sticks is Rs 5,600. What is the price of 3 bats and 4 sticks?
correct answer:- 3
The cost of 6 chocolates and 8 packets of biscuits is Rs 200. What would be the cost of 15 chocolates and 20 packets of biscuits?
correct answer:- 4
Ram is 5 years older than Shyam, who is thrice as old as Arun. If the sum of their ages is 40, then find the age of Ram.
correct answer:- 2
$$\frac{6}{11}$$th of a number is 60% of another number. What is the ratio between the first and the second number?
correct answer:- 5
The average of seven consecutive positive integers is 52. What is the value of the integer in the middle?
correct answer:- 3
Given two variables x and y that satisfy both the linear equations given below,
1. 5x + 6y = 17
2. 3x + 8y = 19
Which of the following options is definitely true?
correct answer:- 2
55% of a number is equal to 3/8th of another number. What is the ratio of the first and second numbers?
correct answer:- 1
If $$4^{a + b} = 1024$$ and $$4^{a - b} = 4$$, then what is the value of a*b?
correct answer:- 3
What is the value of ‘x’ if 1985 - 3x = 4x + 445?
correct answer:- 3
The cost of three apples and two oranges is Rs. 65. The cost of two apples and five oranges is Rs. 80. What is the difference between the cost of ten apples and eight oranges?
correct answer:- 4
A carbon copier requires 27 bundles of paper for 6 days. How many bundles of paper will be required for 14 days?
correct answer:- 3
A student requires 324 pencils in 6 years. How many dozen pencils will he require in 14 years?
correct answer:- 5
When 33.75 is subtracted from three-fifths of a number, it is equal to 45% of the same number. What is one-third of the number?
correct answer:- 5
The total price of 6 pairs of trousers and 5 shirts was Rs. 2,340. The total price of 7 shirts is Rs. 540 more than the total price of 3 trousers. What is the total price of 4 shirts?
correct answer:- 5
The cost of 8 fans and 14 ovens is Rs. 36,520. What is the cost of 12 fans and 21 ovens?
correct answer:- 2
The cost of 36 pens and 42 pencils is Rs . 460/-. What is the cost of 18 pens and 21 pencils?
correct answer:- 1
The cost of 20 pens and 17 pencils is Rs. 418. What is the cost of 60 pens and 51 pencils?
correct answer:- 5
A trader sells 150 metres of cloth for Rs. 6,600, and he sells 300 metres of cloth for Rs. 12,750. How much concession does the trader give per metre of cloth when he sells 300 metres of cloth?
correct answer:- 3
The cost of 20 folders and 15 pens is Rs. 995. What is the cost of 12 folders and 9 pens ?
correct answer:- 2
In a class of 30 students and 2 teachers, each student got sweets that were equal to 20% of the total number of students, and each teacher got sweets that were equal to 30% of the total number of students. How many sweets were there?
correct answer:- 5
If Rs. 97836 is distributed equally amongst 31 children, how much would each child get?
correct answer:- 4
Among five people - A, B, C, D and E — each scoring different marks, only one person scored fewer marks than B. D scored more marks than B but fewer than A. If A did not score the highest marks, then who scored the second-highest marks?
correct answer:- 3
P, Q and R have a certain amount of money with themselves. Q has 25% more than what P has, and R has $${1 \over 5}$$th of what Q has. If P, Q, and R together have Rs. 150, then how much money does P alone have? (in Rs.)
correct answer:- 4
If a and b are real numbers that satisfy these two equations.
$$\dfrac{49}{a + b} + \dfrac{81}{a - b} = 34$$
$$\dfrac{84}{a - b} + \dfrac{245}{a + b} = 63$$
Which of the following statements is definitely true?
correct answer:- 5
Related Articles for Algebra
GMAT Linear Equations questions test your ability to form and solve algebraic equations involving one or two unknowns.
Usually, 2-4 linear equation questions appear in the Quantitative Reasoning section, often mixed with word problems.
Age problems, ratios, mixtures, cost-price and selling price relations, and equation-based comparisons.
Start by learning basic formulas, practice substitution and elimination, and review word problems daily.
Wrong signs, misinterpreting “more than” or “less than,” and forgetting to check your final answer.
Yes, you can download a simple GMAT Linear Equations Formula PDF that includes all key concepts and examples.
Yes, they are foundational. Many higher-level algebra and data sufficiency questions are built on linear equations.
Simplify first, use substitution where possible, and practice regularly to improve calculation speed.