Organise the following marks in a class assessment, in a tabular form.
4, 6, 7, 5, 3, 5, 4, 5, 2, 6, 2, 5, 1, 9, 6, 5, 8, 4, 6, 7
$(i)$. Which number is the highest?
$(ii)$. Which number is the lowest?
$(iii)$. What is the range of the data?
$(iv)$. Find the arithmetic mean.

AcademicMathematicsNCERTClass 7

To do:

We have to organise the given marks in a class assessment, in a tabular form and answer the given questions.

Solution:

The given data is as follows,

4, 6, 7, 5, 3, 5, 4, 5, 2, 6, 2, 5, 1, 9, 6, 5, 8, 4, 6, 7

Let's tabulate the data as shown below.

MarksTally MarksFrequency
1|1
2||2
3|1
4|||3
5
5
6||||4
7||2
8|1
9|1

(i) The highest number is 9.

(ii) The lowest number is 1.

(iii) We know that, Range$=$Highest marks$-$Lowest marks

The range of the data$=$Highest number$-$Lowest number

$=9-1$

$=8$

(iv) Arithmetic mean$=\frac{ \text {Sum of all the marks }}{ \text {Total number of observations }}$

$=\frac{(4+6+7+5+3+5+4+5+2+6+2+5+1+9+6+5+8+4+6+7)}{20}$

$=\frac{100}{20}$

$=5$

raja
Updated on 10-Oct-2022 13:33:20

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