Advertisements
Advertisements
प्रश्न
The distribution of heights (in cm) of 96 children is given below. Construct a histogram and a frequency polygon on the same axes.
| Height (in cm): | 124 to 128 |
128 to 132 |
132 to 136 |
136 to 140 |
140 to 144 |
144 to 148 |
148 to 152 |
152 to 156 |
156 to 160 |
160 to 164 |
| No. of Children: | 5 | 8 | 17 | 24 | 16 | 12 | 6 | 4 | 3 | 1 |
Advertisements
उत्तर
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.
To draw the frequency polygon of the given data using histogram, obtain the mid-points of the upper horizontal side of each rectangle and then join these mid-points of the adjacent rectangles of the histogram by line segments. Obtain the mid-points of two class-intervals of 0 frequencies, i.e. on the horizontal axis, one adjacent to the first, on its left and one adjacent to the last, on its right. These class-intervals are known as imagined class-intervals. Complete the polygon by joining the mid-points of first and last class-intervals to the mid-points of imagined class-intervals adjacent to them. Let us take one vertical division is equal to 4.
The heights of the different rectangles are as following
1. The height of the rectangle corresponding to the class-interval 124-128 is `5/4 = 1.25` big divisions.
2. The height of the rectangle corresponding to the class-interval 128-132 is ` 8/4`=2` big divisions.
3. The height of the rectangle corresponding to the class-interval 132-136 is `17/4 = 4.25` big divisions.
4. The height of the rectangle corresponding to the class-interval 136-140 is `24/4 = 6` big divisions.
5. The height of the rectangle corresponding to the class-interval 140-144 is `16/4 = 4` big divisions.
6. The height of the rectangle corresponding to the class-interval 144-148 is `12/4 = 3` big divisions.
7. The height of the rectangle corresponding to the class-interval 148-152 is `6/4 = 1.5` big divisions.
8. The height of the rectangle corresponding to the class-interval 152-156 is `4/4 =1 ` big divisions.
9. The height of the rectangle corresponding to the class-interval 156-160 is `3/4 = 0.75` big divisions.
10. The height of the rectangle corresponding to the class-interval 160-164 is `1/4 = 0.25 ` big divisions.
The histogram and frequency polygon of the given data is the following:
APPEARS IN
संबंधित 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?
Given below (Fig. below) is the bar graph indicating the marks obtained out of 50 in mathematics paper by 100 students. Read the bar graph and answer the following questions:
(i) It is decided to distribute work books on mathematics to the students obtaining less than 20 marks, giving one workbook to each of such students. If a work book
costs Rs 5, what sum is required to buy the work books?
(ii) Every student belonging to the highest mark group is entitled to get a prize of Rs. 10. How much amount of money is required for distributing the prize money?
(iii) Every student belonging to the lowest mark—group has to solve 5 problems per day. How many problems, in all, will be solved by the students of this group per day?
(iv) State whether true or false.
a. 17% students have obtained marks ranging from 40 to 49.
b. 59 students have obtained marks ranging from 10 to 29.
(v) What is the number of students getting less than 20 marks?
(vi) What is the number of students getting more than 29 marks?
(vii) What is the number of students getting marks between 9 and 40?
(viii) What is the number of students belonging to the highest mark group?
(ix) What is the number of students obtaining more than 19 marks?
The bar graph shown in Fig 23.16 represents the circulation of newspapers in 10 languages. Study the bar graph and answer the following questions:
(i) What is the total number of newspapers published in Hindi, English, Urdu, Punjabi and Bengali?
(ii) What percent is the number of news papers published in Hindi of the total number of newspapers?
(iii) Find the excess of the number of newspapers published in English over those published in Urdu.
(iv) Name two pairs of languages which publish the same number of newspapers.
(v) State the language in which the smallest number of newspapers are published.
(vi) State the language in which the largest number of newspapers are published.
(vii) State the language in which the number of newspapers published is between 2500 and 3500.
(viii) State whether true or false:
a. The number of newspapers published in Malayalam and Marathi together is less than those published in English.
b. The number of newspapers published in Telugu is more than those published in Tamil.
Read the following bar graph and answer the following questions:
(i) What information is given by the bar graph?
(ii) In which year the export is minimum?
(iii)In which year the import is maximum?
(iv)In which year the difference of the values of export and import is maximum?
In a histogram the class intervals or the group are taken along
A histogram is a pictorial representation of the grouped data in which class intervals and frequency are respectively taken along
In a histogram, each class rectangle is constructed with base as
Draw frequency polygons for each of the following frequency distribution:
(a) using histogram
(b) without using histogram
|
C.I |
10 - 30 |
30 - 50 |
50 - 70 | 70 - 90 | 90 - 110 | 110 - 130 | 130 - 150 |
| ƒ | 4 | 7 | 5 | 9 | 5 | 6 | 4 |
Mr. Kapoor compares the prices (in Rs.) of different items at two different shops A and B. Examine the following table carefully and represent the data by a double bar graph.
| Items | Price (in ₹) at the shop A | Price (in ₹) at the shop B |
|
Tea-set |
900 | 950 |
|
Mixie |
700 | 800 |
|
Coffee-maker |
600 | 700 |
|
Dinner set |
600 | 500 |
Read the following bar graph and answer the following questions:
a. What information is given by the graph?
b. Which state is the largest producer of wheat?
c. Which state is the largest producer of sugar?
d. Which state has total production of wheat and sugar as its maximum?
e. Which state has the total production of wheat and sugar minimum?
