Mode questions with solutions are given here for students to help them with their exam preparations. It is one of three measures of central tendency – Mean, mode and median.

Mode represents the data whose frequency is the highest. For example, given a dataset 11, 16, 12, 23, 16, 14, 12, 13, 11, 14, 15, 16, 17, 16, for this dataset we have frequency distribution table:

Number

Frequency

11

2

12

2

13

1

14

2

15

1

16

4

17

1

23

1

We see that 16 occurs the most. Thus, the mode or the modal value of the given data is 16.

Types of the dataset according to multiple modes:

  • Bimodal – two modal values for the given dataset
  • Trimodal – three modal values for the given dataset
  • Multimodal – more than three modal values for the given dataset.

Learn more about Mode.

Following are some important facts about mode:

  • Most occurring data of the given dataset is called the mode or modal value of the dataset.
  • A dataset can have multiple modes; based on this, types of datasets are bimodal, trimodal and multimodal.
  • Mode = 3 Median – 2 Mean
  • If every data in a given dataset occurs just once, then the dataset has no modal value.
  • The modal value is not affected by the highest or lowest value in the dataset.

Mode Questions with Solutions

Now, let us solve a few questions based on mode.

Question 1:

If the ratio of the mode to the median is 2 : 3 for a dataset. Find the ratio of mode to mean.

Solution:

The empirical relationship between mean mode and median is

Mode = 3 Median – 2 Mean.

Let the modal value be 2x, and the median be 3x, then

2x = 3.3x – 2 Mean

⇒ 2 Mean = 9x – 2x

⇒ Mean = 7x/2

∴ Mode : Mean = 2x/(7x/2) = 4/7 = 4 : 7.

Question 2:

Find the mode of the following data:

Value of x

5

10

15

20

25

30

35

Frequency

3

6

10

6

10

5

9

Solution:

From the given frequency distribution table there are two modes, 15 and 25. Hence, the dataset is bimodal.

Question 3:

For any given data, the mean is 45.5, and the median is 43. Find the modal value.

Solution:

We know that,

Mode = 3 Median – 2 Mean

∴ Mode = 3 × 43 – 2 × 45.5

= 129 – 91 = 38.

Mode = 38.

Mode for a grouped data distribution:

To calculate the mode of a grouped data distribution, we need first to determine the modal class.

Modal Class: The class interval which has the maximum frequency.

Let the kth class interval be the modal class. Then mode is given by the following formula:

\(\begin{array}{l}Mode = l +\left [ \frac{f_{k}-f_{k-1}}{2f_{k}-f_{k-1}-f_{k+1}} \right ]\times h\end{array} \)

where,

l = lower limit of the modal class

fk = frequency of the modal class

fk – 1 = frequency of the class before the modal class

fk – 1 = frequency of the class after the modal class

h = Width of each class interval.

Question 4:

Find the mode of the following data distribution:

Classes

10-20

20-30

30-40

40-50

50-60

60-70

70-80

Frequency

12

14

10

13

14

18

10

Solution:

The modal class is 60-70. Now,

l = 60

fk = 18

fk – 1 = 14

fk + 1 = 10

h = 70 – 60 = 10

\(\begin{array}{l}Mode = l +\left [ \frac{f_{k}-f_{k-1}}{2f_{k}-f_{k-1}-f_{k+1}} \right ]\times h\end{array} \)

= 60 + [(18 – 14)/(2 × 18 – 14 – 10)] × 10

= 60 + [4/12] × 10

= 60 + 10/3

= 63.333 (approx).

Question 5:

Find the mode of the following data distribution:

Class-Interval

10-20

20-30

30-40

40-50

50-60

frequency

12

35

45

25

13

Solution:

Clearly, the modal class is 30-40, then

l = 30

fk = 45

fk – 1 = 35

fk + 1 = 25

h = 40 – 30 = 10

\(\begin{array}{l}Mode = l +\left [ \frac{f_{k}-f_{k-1}}{2f_{k}-f_{k-1}-f_{k+1}} \right ]\times h\end{array} \)

= 30 + [(45 – 35)/(2 × 45 – 35 – 25)] × 10

= 30 + [10/30] × 10

= 30 + 10/3

= 100/3 = 33.333.

Also Read:

Question 6:

The mode of the following data is 36. Find the missing frequency in it.

Class Interval

0-10

10-20

20-30

30-40

40-50

Frequency

4

6

9

5

Solution:

Let the missing value be x, since the modal value is 36, therefore the modal class is 30-40.

l = 30

fk = 9

fk – 1 = x

fk + 1 = 5

h = 40 – 30 = 10

\(\begin{array}{l}Mode = l +\left [ \frac{f_{k}-f_{k-1}}{2f_{k}-f_{k-1}-f_{k+1}} \right ]\times h\end{array} \)

⇒ 30 + [(9 – x)/(2 × 9 – x – 5)] × 10 = 36

⇒ 30 + [(9 – x)/(13 – x)] × 10 = 36

⇒ [(9 – x)/(13 – x)] = (36 – 30)/10

⇒ [(9 – x)/(13 – x)] = 6/10

⇒ 10 × (9 – x) = 6(13 – x)

⇒ 90 – 10x = 78 – 6x

⇒ 4x = 12

⇒ x = 3

∴ the missing frequency is 3

Question 7:

Calculate the mode of the following data distribution:

Age (in years)

0-5

5-10

10-15

15-20

20-25

25-30

30-35

Number of patients

6

11

18

24

17

13

5

Solution:

Clearly, the modal class is 15-20, then

l = 15

fk = 24

fk – 1 = 18

fk + 1 = 17

h = 20 – 15 = 5

\(\begin{array}{l}Mode = l +\left [ \frac{f_{k}-f_{k-1}}{2f_{k}-f_{k-1}-f_{k+1}} \right ]\times h\end{array} \)

= 15 + [(24 – 18)/(2 × 24 – 18 – 17)] × 5

= 15 + [6/13] × 5

= 15 + 30/13

= 17.3 years (approx.)

Question 8:

Calculate the mode of the following data distribution:

Marks in %

40-50

50-60

60-70

70-80

80-90

90-100

Number of students

5

4

7

8

6

5

Solution:

Clearly, the modal class is 70-80, then

l = 70

fk = 8

fk – 1 = 7

fk + 1 = 6

h = 80 – 70 = 10

\(\begin{array}{l}Mode = l +\left [ \frac{f_{k}-f_{k-1}}{2f_{k}-f_{k-1}-f_{k+1}} \right ]\times h\end{array} \)

= 70 + [(8 – 7)/(2 × 8 – 7 – 6)] × 10

= 70 + [1/3] × 10

= 70 + 10/3

= 220/3 = 73.34 (approx.)

Question 9:

Calculate the mode of weekly wages from the following frequency distribution:

Wages (in ₹)

Number of workers

30-40

10

40-50

20

50-60

40

60-70

16

70-80

8

80-90

6

Solution:

Clearly, the modal class is 50-60, then

l = 50

fk = 40

fk – 1 = 20

fk + 1 = 16

h = 60 – 50 = 10

\(\begin{array}{l}Mode = l +\left [ \frac{f_{k}-f_{k-1}}{2f_{k}-f_{k-1}-f_{k+1}} \right ]\times h\end{array} \)

= 50 + [(40 – 20)/(2 × 40 – 20 – 16)] × 10

= 50 + [20/44] × 10

= 50 + 50/11

= 600/3 = 54.55 (approx.)

Question 10:

Calculate the mode of the following data distribution:

Class Interval

10-14

14-18

18-22

22-26

26-30

30-34

34-38

38-42

Frequency

8

6

11

20

25

22

10

4

Solution:

Clearly, the modal class is 26-30, then

l = 26

fk = 25

fk – 1 = 20

fk + 1 = 22

h = 30 – 26= 4

\(\begin{array}{l}Mode = l +\left [ \frac{f_{k}-f_{k-1}}{2f_{k}-f_{k-1}-f_{k+1}} \right ]\times h\end{array} \)

= 26 + [(25 – 20)/(2 × 25 – 20 – 22)] × 4

= 26 + [⅝] × 4

= 26 + 5/2

= 57/2= 28.5.

Related Articles

Median Questions

Compound Interest Questions

Permutation Combination Questions

Area Related Circles Questions

Practice Questions on Mode

1. Mode of the scores 4, 4, 6, 6, 2, 3, 3, 3, 3, 3, 4, 5, 6, 5, 6, 6 is _______.

2. If the mode of the given data set 3, 4, 3, 5, 4, 6, 6 and x is 4. Find the value of x.

3. Find the mode of the following data distribution:

Class-Interval

Frequency

0-5

2

5-10

10

10-15

8

15-20

6

20-25

4

4. Find the mode of the discrete data:

Variable

Frequency

Variable

Frequency

1

5

5

11

2

4

6

13

3

6

7

9

4

8

8

10

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