NCERT Solutions for Class 7 Maths Chapter 3 Data Handling Ex 3.2

NCERT TEXTBOOK EXERCISES

Question 1. The scores in mathematics test (out of 25) of 15 students is as follows:
19, 25, 23, 20, 9, 20, 15, 10, 5, 16, 25, 20, 24, 12, 20
Find the mode and median of this data. Are they the same?

Solution:

For Median. We arrange the data in ascending order, we get
5, 9, 10, 12, 15, 16, 19, 20,
20, 20, 20, 23, 24, 25, 25
Median is the middle observation.
Therefore, 20 is the median.
For Mode.
Mode = Observation with highest frequency = 20
Yes, they are the same.

Question 2. The runs scored in a cricket match by 11 players is as follows:
6, 15, 120, 50, 100, 80, 10, 15, 8, 10, 15.
Find the mean, mode, and median of this data. Are the three same?

Solution:

(ii) For Median. We arrange the data in ascending order, we get
6, 8, 10, 10, 15, 15, 15, 50, 80, 100, 120
Median is the middle observation. Therefore, 15 is the median.

(iii) For Mode. Mode = observation with highest frequency = 15
No! They are not the same.

Question 3. The weights (in kg.) of 15 students of a class are:
38, 42, 35, 37, 45, 50, 32, 43,
43, 40, 36, 38, 43, 38, 47

Find the mode and median of this data.
Is there more than one mode?

Solution:

(i) For Median. We arrange the data in ascending order, we get
32, 35, 36, 37, 38, 38, 38, 40, 42, 43, 43,
43, 45, 47, 50
Median is the middle observation.
Therefore, 40 kg is the median.
For Mode. Mode = observation with highest frequency = 38 kg and 43 kg.
(ii) Yes! there are 2 (more than one) modes.

Question 4. Find the mode and median of the data:
13, 16, 12, 14, 19, 12, 14, 13, 14.

Solution:

For Median. We arrange the data in ascending order, we get 12, 12, 13, 13, 14, 14, 14, 16, 19.
Median is the middle observation.
Therefore, 14 is the median.
For Mode. Mode = observation with highest frequency = 14.

Question 5. Tell whether the statement is true or false:

The mode is always one of the numbers in data.
The mean is one of the numbers in a data.
The median is always one of the numbers in a data.
The data 6, 4, 3, 8, 9, 12, 13, 9 has a mean of 9.

Solution:

True
False
True
False.