Advertisements
Advertisements
Question
Construct a histogram for the following data:
| Monthly School fee (in Rs): |
30-60 | 60-90 | 90-120 | 120-150 | 150-180 | 180-210 | 210-240 |
| No of Schools | 5 | 12 | 14 | 18 | 10 | 9 | 4 |
Advertisements
Solution
To represent the given data by a histogram, we first draw horizontal and vertical axes. Let us consider that the horizontal and vertical axes represent the class-limits and the frequencies of the class-intervals respectively.
The given data is a continuous grouped frequency distribution with equal class-intervals. Construct rectangles with class-intervals as bases and respective frequencies as heights. It should be noted that the scale for horizontal axis may not be same as the scale for vertical axis. Let us take one vertical division is equal to 3 rupees.
The heights of the different rectangles are as following
1. The height of the rectangle corresponding to the class-interval 30-60 is `5/3=1.66` big divisions.
2. The height of the rectangle corresponding to the class-interval 60-90 is `12/3 = 4` big divisions.
3. The height of the rectangle corresponding to the class-interval 90-120 is `14/3 = 4.66 ` big divisions.
4. The height of the rectangle corresponding to the class-interval 120-150 is `18/3=6` big divisions.
5. The height of the rectangle corresponding to the class-interval 150-180 is `10/30= 3.33` big divisions.
6. The height of the rectangle corresponding to the class-interval 180-210 is `9/3 = 3` big divisions.
7. The height of the rectangle corresponding to the class-interval 210-240 is `4/3 = 1.33` big divisions.
The histogram of the given data is the following:
APPEARS IN
RELATED QUESTIONS
The following table gives the life times of 400 neon lamps:-
| Life time (in hours) | Number of lamps |
| 300 - 400 | 14 |
| 400 - 500 | 56 |
| 500 - 600 | 60 |
| 600 - 700 | 86 |
| 700 - 800 | 74 |
| 800 - 900 | 62 |
| 900 - 1000 | 48 |
- Represent the given information with the help of a histogram.
- How many lamps have a life time of more than 700 hours?
Read the following bar graph and answer the following questions:
(i) What information is given by the bar graph?
(ii) Which state is the largest producer of rice?
(iii) Which state is the largest producer of wheat?
(iv) Which state has total production of rice and wheat as its maximum?
(v) Which state has the total production of wheat and rice minimum?
The following bar graph (Fig. 23. 1 4) represents the heights (in cm) of 50 students of Class XI of a particular school. Study the graph and answer the following questions:
(i) What percentage of the total number of students have their heights more than 149cm?
(ii) How many students in the class are in the range of maximum height of the class?
(iii) The school wants to provide a particular type of tonic to each student below the height
of 150 cm to improve his height. If the cost of the tonic for each student comes out to be Rs. 55, how much amount of money is required?
(iv) How many students are in the range of shortest height of the class?
(v) State whether true or false:
a. There are 9 students in the class whose heights are in the range of 155 - 159 cm.
b. Maximum height (in cm) of a student in the class is 17.
c. There are 29 students in the class whose heights are in the range of 145- 154 cm.
d. Minimum height (in cm) of a student is the class is in the range of 140 – 144 cms.
e. The number of students in the class having their heights less than 150 cm is 12.
f. There are 14 students each of whom has height more than 154. cm.
Read the bar graph given in Fig. 23.19 and answer the following questions:
(i) What information is given by the bar graph?
(ii) In which years the areas under the sugarcane crop were the maximum and the minimum?
(iii) State whether true or false:
The area under the sugarcane crop in the year 1982 - 83 is three times that of the year 1950 - 51
The income and expenditure for 5 years of a family is given in the following data:
| Years | 1995-96 | 1996-97 | 1997-98 | 1998-99 | 1999-2000 |
| Income (Rs. inthousands) |
100 | 140 | 150 | 170 | 210 |
| Expenditure (Rs. in thousands) |
80 | 130 | 145 | 160 | 190 |
Represent the above data by a gar graph.
The expenditure (in 10 crores of rupees) on health by the Government of India during the various five year plans is shown below:
| Plans: | I | II | III | IV | V | VI |
| Expenditure on health (in 10 crores of rupees) |
7 | 14 | 23 | 34 | 76 | 182 |
Construct a bar graph to represent the above data.
Students of a small school use different modes of travel to school as shown below:
| Mode | Bus | Car | Bicycle | Auto | On foot |
| No. of students | 142 | 98 | 50 | 34 | 16 |
Draw a suitable bar graph.
The following tables show the mode of transport used by boys and girls for going to the same school.
| Bus | Bicycle | Walking | Other sources | |
|
Number of boys |
80 | 60 | 20 | 85 |
|
Number of girls |
90 | 75 | 35 | 60 |
Draw a double bar graph representing the above data.
Is it correct to say that in a histogram, the area of each rectangle is proportional to the class size of the corresponding class interval? If not, correct the statement.
Draw a histogram to represent the following grouped frequency distribution:
| Ages (in years) | Number of teachers |
| 20 – 24 | 10 |
| 25 – 29 | 28 |
| 30 – 34 | 32 |
| 35 – 39 | 48 |
| 40 – 44 | 50 |
| 45 – 49 | 35 |
| 50 – 54 | 12 |
