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: