NCTB Class 8 Math Chapter Eleven Exercise 11 Solution

NCTB Class 8 Math Chapter Eleven Exercise 11 Solutions by Math Expert. Bangladesh Board Class 8 Math Solution Chapter Eleven Information & Data Exercise 11 Solution.

Board

NCTB
Class

8

Subject

Mathematics
Chapter

11

Chapter Name

Information & Data
Exercise

11 Solution

 

Exercise 11

2>Which one of the following indicates the data included in a class ? (a) Frequency of the class

(b) Mid-point of the class

(c) Limit of the class   

(d) Cumulative frequency

Ans: (a)

3> What is the arithmetic mean of the numbers 8, 12, 16, 17, 20 ?

(a) 10.5

(b) 12.5

(c) 13.6

(d) 14.6

Ans: (d)

4> What is the median of the numbers 10, 12, 14, 18, 19, 25 ?

(a) 11.5

(b) 14.6

(c) 16

(d) 18.6

Ans: (c)

5> What are the modes of the numbers 6, 12, 7, 12, 11, 12, 11, 7, 11 ? (a) 11 and 7

(b) 11 and 12

(c) 7 and 12

(d) 6 and 7

Ans: (b)

The frequency distribution table of the marks obtained in Mathematics by 40 students of your class is as follows:

Class interval 41-55 56-70 71-85 86-100
Frequency 6 10 20 4

 

6> Which one is the class interval ?

(a) 5

(b) 10

(c) 12

(d) 15

Ans: (d)

7> Which one is mid-value of the 2nd class ?

(a) 45

(b) 63

(c) 78

(d) 93

Ans: (b)

8> Which is the lower value of the class of mode in the table above ?

(a) 41

(b) 56

(c) 71

(d) 86

Ans: (c) 71

9> The marks obtained by 25 students in the annual examination arc given below: 72,85, 78,84, 78, 75,69,67,88,80, 74, 77, 79,69, 74, 73,83,65, 75,69, 63, 75, 86, 66, 71.

(a) Find the arithmetic mean of the marks obtained directly.

(b) Make the frequency distribution table with 5 as class interval and find the arithmetic mean from the table.

(c) Show the difference between the arithmetic means found in two different ways.

Ans:  total sum of above number = 1875

Therefore arithmetic mean= 1875/25

= 75

10> A table is given below. Find the arithmetic mean. Draw the histogram of the data

Marks obtained 6-10 11-15 16-20 21-25 26-30 31-35 36-40 41-45
Frequency 5 17 30 38 35 10 7 3

 Ans:

11> Find the arithmetic mean from the following table:

Daily Income 2210 2215 2220 2225 2230 2235 2240 2245 2250
Frequency 2        3 5 7 6 5 5 4 3

 Ans:

12> Weekly savings (in taka) of 40 house wives are as follows: 155, 173, 166, 143, 168, 160, 156, 146, 162, 158, 159, 148, 150, 147, 132, 156, 140, 155, 145, 135, 151, 141, 169, 140, 125, 122, 140, 137, 175, 145, 150, 164, 142, 156, 152, 146, 148, 157, 167.

Ans:

13> Find the arithmetic mean, median and mode of weekly savings.  Find the arithmetic mean and draw the histogram of the data:

Age (in years) 5-6 7-8 9-10 11-12 13-14 15-16 17-18
Frequency 25 27 28 31 29 28 22

 Ans:

14> The frequency distribution table of monthly wages of 100 labours of an industry is given below. What is the arithmetic mean of monthly wages of the labours ? Draw the histogram of the following data.

Ans:

15> Marks obtained in English by 30 students of class VII are : 45, 42, 60, 61, 58, 53, 48, 52, 51, 49, 73, 52, 57, 71, 64, 49, 56, 48, 67, 63, 70, 59, 54, 46, 43, 56, 59, 43, 68, 52.

(a) What are the numbers of classes with 5 as class interval ?

(b) Make a frequency distribution table with 5 as class interval.

(c) Find the arithmetic mean from the table.

Ans:

16> Daily savings of 50 students are given below:

Saving (in taka) 41-50 51-60 61-70 71-80 81-90 91-100
Frequency 6 8 13 10 8 5

(a) Make a cumulative frequency table.

(b) Find the arithmetic table from the table.

Ans:

17> The favourite fruits of 200 students are given in the table. Draw a pie chart:

Fruit Mango jackfruit Litchi Jambolic
Number of students 70 30 80 20

 

Ans:  

18> The subjects chosen by 720 students are presented in the pie-chart. Express the numbers.

Bengali – 90°

English – 30°

Math-50°

Science 60°

Religion – 80°

Music 50°

Total= 360°

Ans:

19> The frequency distribution table of the marks obtained in mathematics by 50 students is as follows:

Marks obtained 60 65 70 75 80 85
Frequency 5 8 11 15 8 3

a> find out the Median

b>Find out the arithmetic mean.

c>Draw the pie chart of the given data.

 Ans: 

20> A table is given below :

Class Interval 20-29 30-39 40-49 50-59 60-69
Frequency 10 6 18 12 8

 a> Find the median of the data: 7, 5, 4, 9, 3, 8

b> Find out the Arithmetic mean from the data (table)

c> Draw the Histogram on the data.

Ans:

21> Weekly savings (in taka) of 40 house-wives are given below : 155, 173, 166, 143, 168, 160, 156, 146, 162, 158, 159, 148, 150, 147, 132, 136, 154, 140, 155, 145, 135, 151, 141, 169, 140, 125, 122, 140, 137, 175, 145, 150, 164, 142, 156, 152, 146, 148, 157, 167.

A> Arrange the data in ascending order.

B> Find out the Median and Mode.

C> Make a frequency distribution table with 5 as class interval and find out the Arithmetic mean.

Ans:

Updated: March 31, 2021 — 2:35 pm

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