Mode is one of the most important measures of central tendency in statistics and is used to identify the value that appears most frequently in a dataset. For example, if the marks scored by students are 12, 15, 15, 18, and 20, then 15 is the mode because it occurs the most. In mathematics and statistics, mode helps us understand patterns, trends, and the most common observation in a set of values. It is widely used in school mathematics, data handling, business analysis, and research. Questions based on mode are commonly asked in Class 9-10 Maths, statistics chapters, and competitive exams like SSC, Bank, CUET, CAT, and other quantitative aptitude tests. In this article, we will understand the mode of grouped and ungrouped data, formulas, solved examples, and how to calculate it easily using a mode calculator.

Mode is one of the most important measures of central tendency in statistics. It represents the value that occurs most frequently in a dataset. In simple words, mode tells us which observation repeats the most.
It is widely used in mathematics, statistics, business analysis, surveys, and research to identify the most common value or trend in a group of data.
Mode is the value that appears the maximum number of times in a set of data.
If one observation occurs more frequently than all others, that observation is called the mode.
For example:
$2,\ 4,\ 4,\ 6,\ 7,\ 4,\ 8$
Here, 4 appears three times, while the other numbers appear once.
Therefore:
Mode $= 4$
Mode is useful in everyday situations where we want to identify the most common item or repeated value.
Examples include:
Suppose students choose their favourite fruit:
Apple, Mango, Banana, Mango, Orange, Mango
Since Mango appears most frequently,
Mode = Mango
Mode helps us understand what occurs most often in a dataset. It is useful when identifying common patterns, repeated responses, or popular choices.
Mode is important because:
Ungrouped data means data listed in its original form without class intervals. To find mode in ungrouped data, we simply identify the value with the highest frequency.
The mode of ungrouped data is the observation that appears most frequently among all the values.
If no number repeats, then the data may have no mode.
To calculate mode in ungrouped data:
Find the mode of:
$3,\ 5,\ 7,\ 5,\ 8,\ 5,\ 2,\ 7$
Frequency table:
| Observation | Frequency |
|---|---|
| 2 | 1 |
| 3 | 1 |
| 5 | 3 |
| 7 | 2 |
| 8 | 1 |
5 occurs most frequently.
Therefore:
Mode $= 5$
Find the mode of:
$12,\ 15,\ 15,\ 18,\ 20,\ 15,\ 12$
| Observation | Frequency |
|---|---|
| 12 | 2 |
| 15 | 3 |
| 18 | 1 |
| 20 | 1 |
Hence,
Mode $= 15$
When observations are arranged into class intervals along with frequencies, it is called grouped data. In this case, mode is found using a formula.
The mode of grouped data is the value corresponding to the class interval having the highest frequency.
The class with the highest frequency is called the modal class.
The formula for mode of grouped data is:
$Mode = l + \frac{f_1-f_0}{2f_1-f_0-f_2}\times h$
Where:
| Symbol | Meaning |
|---|---|
| $l$ | Lower limit of modal class |
| $f_1$ | Frequency of modal class |
| $f_0$ | Frequency preceding modal class |
| $f_2$ | Frequency succeeding modal class |
| $h$ | Class width |
Follow these steps:
Find the mode of the following grouped data:
| Class Interval | Frequency |
|---|---|
| 0-10 | 5 |
| 10-20 | 8 |
| 20-30 | 12 |
| 30-40 | 7 |
| 40-50 | 3 |
Highest frequency = 12
So modal class = $20-30$
Thus:
$l = 20$
$f_1 = 12$
$f_0 = 8$
$f_2 = 7$
$h = 10$
Using formula:
$Mode = l + \frac{f_1-f_0}{2f_1-f_0-f_2}\times h$
$= 20 + \frac{12-8}{2(12)-8-7}\times10$
$= 20 + \frac{4}{24-15}\times10$
$= 20 + \frac{4}{9}\times10$
$= 20 + 4.44$
$= 24.44$
Therefore,
Mode $= 24.44$
The formula for mode depends on whether the data is ungrouped or grouped. For ungrouped data, mode can be found by observation, while for grouped data, we use a mathematical formula.
Knowing the correct mode formula makes it easier to solve statistics questions in school exams and quantitative aptitude.
For ungrouped data, there is no fixed algebraic formula. We simply identify the value that occurs most frequently.
Mode = Observation with highest frequency
Find the mode of:
$5,\ 7,\ 8,\ 7,\ 9,\ 7,\ 10$
Frequency:
| Observation | Frequency |
|---|---|
| 5 | 1 |
| 7 | 3 |
| 8 | 1 |
| 9 | 1 |
| 10 | 1 |
Since 7 appears most often,
Mode $= 7$
For grouped frequency distribution, mode is calculated using the formula:
$Mode = l + \frac{f_1-f_0}{2f_1-f_0-f_2}\times h$
This formula gives the approximate value of the mode from grouped data.
Each term in the grouped data mode formula has a specific meaning.
| Symbol | Meaning |
|---|---|
| $l$ | Lower limit of modal class |
| $f_1$ | Frequency of modal class |
| $f_0$ | Frequency of class before modal class |
| $f_2$ | Frequency of class after modal class |
| $h$ | Class size or class width |
| Symbol | Example Value |
|---|---|
| $l$ | 20 |
| $f_1$ | 15 |
| $f_0$ | 9 |
| $f_2$ | 7 |
| $h$ | 10 |
Finding mode is one of the easiest topics in statistics. The method depends on whether the data is grouped or ungrouped.
Follow these steps:
Data:
$4,\ 6,\ 7,\ 6,\ 8,\ 6,\ 10$
6 appears 3 times.
Therefore:
Mode $= 6$
For grouped data:
Use the formula:
$Mode = l + \frac{f_1-f_0}{2f_1-f_0-f_2}\times h$
The modal class is the class interval with the highest frequency.
| Class Interval | Frequency |
|---|---|
| 10-20 | 5 |
| 20-30 | 9 |
| 30-40 | 14 |
| 40-50 | 7 |
Highest frequency = 14
Therefore:
Modal Class = $30-40$
Once modal class is identified, use its lower limit and frequencies in the formula.
A mode calculator helps find the mode quickly without manual calculation. It is useful for checking answers and solving long datasets faster.
A mode calculator is an online tool that calculates the mode of a given dataset automatically.
You simply enter:
and the calculator returns the mode instantly.
To use a mode calculator:
For grouped data:
Suppose data is:
$4,\ 5,\ 5,\ 7,\ 8,\ 5,\ 9$
Input these values into the calculator.
Since 5 occurs three times,
Mode $= 5$
Mode calculators are helpful for students for:
Mean, median, and mode are the three main measures of central tendency. Each represents data differently.
| Measure | Meaning | Formula / Method |
|---|---|---|
| Mean | Average of observations | Sum ÷ Number of observations |
| Median | Middle value of arranged data | Middle observation |
| Mode | Most frequent observation | Highest frequency value |
Data:
$2,\ 3,\ 3,\ 5,\ 7$
Mean:
$\frac{2+3+3+5+7}{5}$
$= \frac{20}{5}$
$= 4$
Median:
Middle value = 3
Mode:
Most frequent value = 3
So:
The choice depends on the type of data.
| Situation | Best Measure |
|---|---|
| To find average marks | Mean |
| To find middle value | Median |
| To find most common value | Mode |
| For survey or category data | Mode |
| For skewed data | Median |
Mode is especially useful when the goal is to identify the most common observation in the dataset.

Mean, median, and mode are the three most important measures of central tendency in statistics. These three are connected through an empirical relationship, which is useful when one of the values is missing and the other two are known.
This relation is widely used in statistics questions in school mathematics, data interpretation, and quantitative aptitude exams.
The empirical relationship between mean, median, and mode is:
$Mode = 3 \times Median - 2 \times Mean$
This formula helps calculate the mode when mean and median are given.
The above formula can be rearranged to find mean:
$Mean = \frac{3 \times Median - Mode}{2}$
This is useful when mode and median are known.
Similarly, the formula can be written to find median:
$Median = \frac{Mode + 2 \times Mean}{3}$
This is used when mean and mode are given.
| To Find | Formula |
|---|---|
| Mode | $Mode = 3 \times Median - 2 \times Mean$ |
| Mean | $Mean = \frac{3 \times Median - Mode}{2}$ |
| Median | $Median = \frac{Mode + 2 \times Mean}{3}$ |
Consider a dataset where:
Mean $= 50$
Median $= 48$
Find the mode.
Using the empirical formula:
$Mode = 3 \times Median - 2 \times Mean$
Substitute the values:
$Mode = 3 \times 48 - 2 \times 50$
$= 144 - 100$
$= 44$
Therefore,
Mode $= 44$
This relation is very useful for quick calculations and solving multiple-choice questions based on measures of central tendency.

The books below are useful for understanding mode in statistics, solving grouped and ungrouped data questions, and practicing exam-level problems. They are suitable for both school students and quantitative aptitude preparation.
| Book Name | Best For | Why It Helps |
|---|---|---|
| NCERT Mathematics Textbook | Class 9-10 students | Covers mode, mean, median, and statistics basics with examples |
| Quantitative Aptitude for Competitive Examinations | SSC, Bank, CUET, aptitude exams | Includes statistics concepts with practice questions on mode |
| Higher Algebra | Advanced mathematics learners | Useful for deeper understanding of mathematical statistics |
| Objective Arithmetic | Competitive exam preparation | Good for MCQs and topic-wise practice |
| Statistics for Economics | Statistics and economics students | Helpful for practical applications of mode and data analysis |
Mode is usually easy to calculate, but a few shortcut tricks can make it faster, especially in exams with limited time.
| Trick | Shortcut |
|---|---|
| Ungrouped data | Count frequency and pick highest repeated value |
| Grouped data | Identify modal class first, then apply formula |
| Modal class shortcut | Class interval with highest frequency |
| No repeated value | Dataset may have no mode |
| Two repeated highest values | Dataset is bimodal |
| More than two repeated highest values | Dataset is multimodal |
| Quick checking | Mode must belong to the dataset in ungrouped data |
These tips can help avoid mistakes while solving statistics questions on mode.
| Tip | Explanation |
|---|---|
| Count carefully | Small frequency mistakes change the answer |
| Arrange data clearly | Makes repeated values easier to spot |
| Check highest frequency twice | Helps confirm the mode |
| Identify modal class before formula | First step in grouped data questions |
| Write symbol values separately | Helps avoid substitution mistakes |
| Compare with mean and median | Useful in data interpretation questions |
| Use calculator for long values | Saves time in grouped data calculations |
This quick formula table is useful for revision before exams and solving statistics problems faster.
| Concept | Formula |
|---|---|
| Mode of Ungrouped Data | Observation with highest frequency |
| Mode of Grouped Data | $Mode = l + \frac{f_1-f_0}{2f_1-f_0-f_2}\times h$ |
| Modal Class | Class interval with highest frequency |
| Mean | $\frac{\sum x}{n}$ |
| Median | Middle observation after arranging data |
| Empirical Relation | $Mode = 3 \times Median - 2 \times Mean$ |
This table works well as a quick revision sheet for students preparing for statistics chapters, school exams, and quantitative aptitude tests.
Q1. The mode of the following data is:
13, 15, 31, 12, 27, 13, 27, 30, 27, 28, 16
Hint:
Mode is the value that appears most frequently in a dataset.
Solution:
Given data:
$13,\ 15,\ 31,\ 12,\ 27,\ 13,\ 27,\ 30,\ 27,\ 28,\ 16$
Count frequency of each value:
| Number | Frequency |
|---|---|
| 12 | 1 |
| 13 | 2 |
| 15 | 1 |
| 16 | 1 |
| 27 | 3 |
| 28 | 1 |
| 30 | 1 |
| 31 | 1 |
27 appears 3 times, which is the highest frequency.
Therefore,
Mode $= 27$
Correct Answer: 27
Q2. For a sample data, mean = 60 and median = 48. For this distribution, the mode is:
Hint:
Use:
$Mode = 3 \times Median - 2 \times Mean$
Solution:
Given:
Mean $= 60$
Median $= 48$
Using formula:
$Mode = 3 \times Median - 2 \times Mean$
$= 3 \times 48 - 2 \times 60$
$= 144 - 120$
$= 24$
Therefore,
Mode $= 24$
Correct Answer: 24
Q3. Find the mode for the given distribution (rounded off to two decimal places).
| Class Interval | Frequency |
|---|---|
| 5-10 | 8 |
| 10-15 | 7 |
| 15-20 | 6 |
| 20-25 | 9 |
| 25-30 | 11 |
| 30-35 | 10 |
Hint:
$Mode = l + \frac{f_1-f_0}{2f_1-f_0-f_2}\times h$
Solution:
Highest frequency = 11
So modal class = $25-30$
Therefore:
$l = 25$
$f_1 = 11$
$f_0 = 9$
$f_2 = 10$
$h = 5$
Using formula:
$Mode = l + \frac{f_1-f_0}{2f_1-f_0-f_2}\times h$
$= 25 + \frac{11-9}{2(11)-9-10}\times5$
$= 25 + \frac{2}{22-19}\times5$
$= 25 + \frac{2}{3}\times5$
$= 25 + 3.33$
$= 28.33$
Therefore,
Mode $= 28.33$
Correct Answer: 28.33
Q4. The following table represents the grouped data for the ages of a sample of people. What is the mode age group?
| Age Group | Frequency |
|---|---|
| 20-30 | 15 |
| 30-40 | 8 |
| 40-50 | 17 |
| 50-60 | 23 |
| 60-70 | 18 |
Solution:
The mode age group is the class interval with the highest frequency.
From the table:
Highest frequency = 23
Corresponding age group = $50-60$
Therefore,
Mode age group = $50-60$
Correct Answer: 50-60
Q5. In a frequency distribution table, the mode is:
Solution:
In a frequency distribution table, the mode is the value corresponding to the class interval with the highest frequency.
It represents the most frequently occurring observation in the dataset.
Therefore, mode is determined from the class having maximum frequency.
Correct Answer: The value in the class with the highest frequency
Q6. What is the mode of the ungrouped data:
$18,\ 22,\ 25,\ 18,\ 21,\ 22,\ 22,\ 25,\ 18,\ 25$
Solution:
Frequency table:
| Number | Frequency |
|---|---|
| 18 | 3 |
| 22 | 3 |
| 25 | 3 |
| 21 | 1 |
The highest frequency is 3.
Values with frequency 3 are:
Since more than one value has the highest frequency, the data is multimodal.
Correct Answer: All of the above
Q7. What is the mode of the given data?
$5,\ 7,\ 9,\ 7,\ 3,\ 7,\ 5,\ 7,\ 8,\ 6,\ 7$
Hint:
Mode is the observation with the highest frequency.
Solution:
Given data:
$5,\ 7,\ 9,\ 7,\ 3,\ 7,\ 5,\ 7,\ 8,\ 6,\ 7$
Count frequency:
| Number | Frequency |
|---|---|
| 3 | 1 |
| 5 | 2 |
| 6 | 1 |
| 7 | 5 |
| 8 | 1 |
| 9 | 1 |
7 appears 5 times, which is the highest.
Therefore,
Mode $= 7$
Correct Answer: 7
Below are some important quantitative aptitude topics frequently covered in mathematics and aptitude exams. Practicing these topics regularly can help improve concept clarity, calculation accuracy, and overall exam performance.
Frequently Asked Questions (FAQs)
Mode is the value that appears most frequently in a dataset. It represents the most common observation among all the values. Unlike the mean and median, the mode can be used for both numerical and categorical data. A dataset may have one mode (unimodal), more than one mode (bimodal or multimodal), or no mode at all if no number repeats.
Central tendency refers to the statistical measure that identifies a single value as representative of an entire dataset. This value is considered the central point around which the data tends to cluster.
Central tendency provides a summary statistic that represents the centre point or typical value of a dataset.
The three most common measures of central tendency are:
Mean
Median
Mode

Yes. There can be more than one mode for a given data set. That set is called Multimodal, which means a set with multiple modes.
Example: In the dataset, 1, 1, 1, 2, 3, 2, 3, 3, 4, the most common values are 1 and 3. (both repeat 3 times)
So, the mode of the dataset is 1 and 3.
The difference between the highest and lowest number of a dataset is called the range of that dataset.
Example:
In the dataset, 10, 12, 11, 10, 15, 20, 19, 21, 11, 9, 10
Highest value = 21
Lowest value = 9
So, the range of the dataset is 21 - 9 = 12
The formula for mode of grouped data is:
$Mode = l + \frac{f_1-f_0}{2f_1-f_0-f_2}\times h$
Where: