Advertisements
Advertisements
प्रश्न
The length of 40 leaves of a plant are measured correct to one millimetre, and the obtained data is represented in the following table:-
| Length (in mm) | Number of leaves |
| 118 - 126 | 3 |
| 127 - 135 | 5 |
| 136 - 144 | 9 |
| 145 - 153 | 12 |
| 154 - 162 | 5 |
| 163 - 171 | 4 |
| 172 - 180 | 2 |
- Draw a histogram to represent the given data. [Hint: First make the class intervals continuous]
- Is there any other suitable graphical representation for the same data?
- Is it correct to conclude that the maximum number of leaves are 153 mm long? Why?
Advertisements
उत्तर
(i) It can be observed that the length of leaves is represented in a discontinuous class interval having a difference of 1 in between them. Therefore, 1/2 = 0.5 has to be added to each upper class limit and also have to subtract 0.5 from the lower class limits so as to make the class intervals continuous.
| Length (in mm) | Number of leaves |
| 117.5 − 126.5 | 3 |
| 126.5 − 135.5 | 5 |
| 135.5 − 144.5 | 9 |
| 144.5 − 153.5 | 12 |
| 153.5 − 162.5 | 5 |
| 162.5 − 171.5 | 4 |
| 171.5 − 180.5 | 2 |
Taking the length of leaves on x-axis and the number of leaves on y-axis, the histogram of this information can be drawn as above.
Here, 1 unit on the y-axis represents 2 leaves.
(ii) Other suitable graphical representation of this data is frequency polygon.
(iii) No, as maximum number of leaves (i.e., 12) has their length in between 144.5 mm and 153.5 mm. It is not necessary that all have their lengths as 153 mm.
APPEARS IN
संबंधित प्रश्न
Given below are the seats won by different political parties in the polling outcome of a state assembly elections:-
| Political Party | A | B | C | D | E | F |
| Seats Won | 75 | 55 | 37 | 29 | 10 | 37 |
- Draw a bar graph to represent the polling results.
- Which political party won the maximum number of seats?
The following table gives the distribution of students of two sections according to the mark obtained by them:-
| Section A | Section B | ||
| Marks | Frequency | Marks | Frequency |
| 0 - 10 | 3 | 0 - 10 | 5 |
| 10 - 20 | 9 | 10 - 20 | 19 |
| 20 - 30 | 17 | 20 - 30 | 15 |
| 30 - 40 | 12 | 30 - 40 | 10 |
| 40 - 50 | 9 | 40 - 50 | 1 |
Represent the marks of the students of both the sections on the same graph by two frequency polygons. From the two polygons compare the performance of the two sections.
The runs scored by two teams A and B on the first 60 balls in a cricket match are given below:
| Number of balls | Team A | Team B |
| 1 - 6 | 2 | 5 |
| 7 - 12 | 1 | 6 |
| 13 - 18 | 8 | 2 |
| 19 - 24 | 9 | 10 |
| 25 - 30 | 4 | 5 |
| 31 - 36 | 5 | 6 |
| 37 - 42 | 6 | 3 |
| 43 - 48 | 10 | 4 |
| 49 - 54 | 6 | 8 |
| 55 - 60 | 2 | 10 |
Represent the data of both the teams on the same graph by frequency polygons.
[Hint: First make the class intervals continuous.]
Read the bar graph given in Fig. 23.22 and answer the following questions:
(i) What information is given by the bar graph?
(ii) Which Doordarshan centre covers maximum area? Also tell the covered area.
(iii) What is the difference between the areas covered by the centres at delhi and Bombay?
(iv) Which Doordarshan centres are in U.P State? What are the areas covered by them?
Draw, in the same diagram, a histogram and a frequency polygon to represent the following data which shows the monthly cost of living index of a city in a period of 2 years:
| Cost of living index: |
440-460 | 460-480 | 480-500 | 500-520 | 520-540 | 540-560 | 560-580 | 580-600 |
| No. of months: | 2 | 4 | 3 | 5 | 3 | 2 | 1 | 4 |
Construct a frequency polygon for the following data:
| Class-Intervals | 10-14 | 15-19 | 20-24 | 25-29 | 30-34 |
| Frequency | 5 | 8 | 12 | 9 | 4 |
For the following table, draw a bar-graph
| A | B | C | D | E | F |
| 230 | 400 | 350 | 200 | 380 | 160 |
Mr. Mirza’s monthly income is Rs. 7,200. He spends Rs. 1,800 on rent, Rs. 2,700 on food, Rs. 900 on the education of his children; Rs. 1,200 on Other things and saves the rest.
Draw a pie-chart to represent it.
In a diagnostic test in mathematics given to students, the following marks (out of 100) are recorded:
46, 52, 48, 11, 41, 62, 54, 53, 96, 40, 98, 44
Which ‘average’ will be a good representative of the above data and why?
Following table shows a frequency distribution for the speed of cars passing through at a particular spot on a high way:
| Class interval (km/h) | Frequency |
| 30 – 40 | 3 |
| 40 – 50 | 6 |
| 50 – 60 | 25 |
| 60 – 70 | 65 |
| 70 – 80 | 50 |
| 80 – 90 | 28 |
| 90 – 100 | 14 |
Draw a histogram and frequency polygon representing the data above.
