Courses
Courses for Kids
Free study material
Offline Centres
More
Store Icon
Store

Unitary Method Explained with Concept and Applications

Reviewed by:
ffImage
hightlight icon
highlight icon
highlight icon
share icon
copy icon

What is the Unitary Method Formula Steps and Solved Examples

The concept of unitary method plays a key role in mathematics and is widely applicable to both real-life situations and exam scenarios. Students use the unitary method in maths to solve questions related to ratios, proportions, costs, time and work, and speed. This approach makes calculations simpler and faster for a wide range of problems.


What Is Unitary Method?

The unitary method in maths is a technique used to find the value of a single unit from the value of multiple units (or vice versa). Once the value for one unit is found, you can calculate the value for any other number of units by simple multiplication. You’ll find this concept applied in areas such as cost calculation, ratio and proportion, and percentage problems.


Key Formula for Unitary Method

Here’s the standard formula:
If the value of n units = A,
then, value of 1 unit = A ÷ n;
value of m units = (A ÷ n) × m


Cross-Disciplinary Usage

The unitary method is not only useful in maths but also plays an important role in Physics, Computer Science, and daily logical reasoning. For example, it is used in speed-distance-time problems, collaborative work, or making sense of ratios in chemical mixtures. Students preparing for JEE or NEET often see its relevance in applied and data interpretation questions.


Step-by-Step Illustration

Let’s solve an example using the unitary method:

Suppose 8 markers cost ₹120. What is the cost of 5 markers?

1. Value of 8 markers = ₹120

2. Find the cost of 1 marker: ₹120 ÷ 8 = ₹15

3. Cost of 5 markers: ₹15 × 5 = ₹75

So, 5 markers will cost ₹75.


Speed Trick or Quick Shortcut

Here’s a quick shortcut for the unitary method in common exam scenarios:

Time & Work Example: If A can finish a task in 6 days, and B can do the same in 4 days, how long will they take if working together?

1. Work done by A in 1 day: 1 ÷ 6 = 1/6

2. Work done by B in 1 day: 1 ÷ 4 = 1/4

3. Combined work per day: 1/6 + 1/4 = (2+3)/12 = 5/12

4. Total time together = 1 ÷ (5/12) = 12/5 = 2.4 days

Tricks like solving for ‘one unit’ streamlines many word problems and is encouraged in school and competitive exams. Vedantu’s sessions share more such methods to help boost your marks efficiently.


Try These Yourself

  • 8 apples cost ₹200. What is the cost of 3 apples?
  • If 2 pens cost ₹34, how many pens can you buy with ₹170?
  • A machine fills 300 bottles in 5 hours. How many bottles in 8 hours?
  • If a cyclist covers 60 km in 3 hours, what is his speed per hour?

Frequent Errors and Misunderstandings

  • Forgetting to first calculate the value of a single unit before moving to the required units.
  • Mixing up direct and inverse variation, especially in time & work or speed problems.
  • Arithmetic errors like dividing incorrectly or confusing units.

Relation to Other Concepts

The idea of unitary method closely connects with ratios and proportions as well as percentage. Mastering this method helps you simplify more complex chapters related to financial maths, speed-time-distance, and collaborative work.


Classroom Tip

A simple way to remember the unitary method: “First find the value of one, then multiply for many.” Draw a table or chart, with knowns on the left and unknowns on the right, as teachers at Vedantu often suggest to make the process error-free.


Wrapping It All Up

We explored the unitary method—from its definition and formula to examples, common mistakes, and its connection to other maths ideas. With practice and the right approach, you’ll solve such word problems quickly and gain confidence in all related chapters. For more practice, check out the Simple Interest and Speed Formula on Vedantu.


FAQs on Unitary Method Explained with Concept and Applications

1. What is the unitary method in maths?

The unitary method is a technique used to find the value of a single unit first and then calculate the value of multiple units from it. It is commonly used in ratio, proportion, cost, speed, and time problems. The basic idea is:

  • Step 1: Find the value of 1 unit.
  • Step 2: Multiply or divide to find the required number of units.
This method simplifies calculations by reducing problems to a single-unit comparison.

2. What is the formula for the unitary method?

The basic formula of the unitary method is: Value of required units = (Given value ÷ Given units) × Required units. Here:

  • Given value ÷ Given units gives the value of 1 unit.
  • Multiply by the required number of units.
This formula works for cost, quantity, distance, and similar proportional problems.

3. How do you solve questions using the unitary method?

To solve a problem using the unitary method, first find the value of one unit and then calculate the required value. Follow these steps:

  • Step 1: Identify the given quantity and value.
  • Step 2: Divide to find the value of 1 unit.
  • Step 3: Multiply by the required number of units.
Example: If 5 pens cost ₹50, then 1 pen costs 50 ÷ 5 = ₹10. So, 8 pens cost 10 × 8 = ₹80.

4. Why is the unitary method important in maths?

The unitary method is important because it helps solve proportion and comparison problems easily by reducing them to one unit. It is widely used in:

  • Cost and price calculations
  • Speed, time, and distance problems
  • Ratio and proportion questions
  • Percentage and profit–loss problems
It builds a strong foundation for understanding proportional reasoning in mathematics.

5. What is an example of the unitary method in daily life?

A common daily life example of the unitary method is calculating total cost from unit price. For example:

  • If 1 kg of apples costs ₹120,
  • Then 4 kg costs 120 × 4 = ₹480.
Here, the cost of one unit (1 kg) is used to find the cost of multiple units.

6. What is the difference between unitary method and ratio method?

The unitary method finds the value of one unit first, while the ratio method directly compares two quantities using proportions. In the unitary method:

  • You calculate the value of 1 unit and scale up or down.
In the ratio method:
  • You set up a proportion like a/b = c/x and solve for the unknown.
Both methods solve proportional problems, but the unitary method is often simpler for beginners.

7. Can the unitary method be used for speed, time, and distance problems?

Yes, the unitary method can be used to solve speed, time, and distance problems by finding the value of one unit first. For example:

  • If a car travels 120 km in 3 hours,
  • Distance in 1 hour = 120 ÷ 3 = 40 km.
So, speed = 40 km/h. This method simplifies calculations involving proportional relationships.

8. How is the unitary method used in profit and loss problems?

The unitary method is used in profit and loss to find cost or selling price per unit first. For example:

  • If 10 items cost ₹500, cost of 1 item = 500 ÷ 10 = ₹50.
  • If profit per item is ₹5, selling price per item = 50 + 5 = ₹55.
This approach helps calculate total profit or selling price easily.

9. What are the common mistakes in the unitary method?

Common mistakes in the unitary method usually involve incorrect division or wrong unit interpretation. These include:

  • Dividing in the wrong order
  • Forgetting to find the value of 1 unit first
  • Mixing up units (e.g., hours and minutes)
  • Calculation errors in multiplication
Carefully identifying units and checking calculations helps avoid these errors.

10. How do you know when to use the unitary method?

Use the unitary method when a problem involves proportional relationships and asks for the value of a different number of units. It is suitable when:

  • A direct relationship exists between two quantities
  • You are given value for some units and need value for other units
  • The quantities increase or decrease proportionally
If the relationship is direct and consistent, the unitary method is an effective solution strategy.