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
Read the bar graph shown in Fig. 23.8 and answer the following questions:

(i) What is the information given by the bar graph?
(ii) How many tickets of Assam State Lottery were sold by the agent?
(iii) Of which state, were the maximum number of tickets sold?
(iv) State whether true or false.
The maximum number of tickets sold is three times the minimum number of tickets sold.
(v) Of which state were the minimum number of tickets sold?
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.
The following table shows the daily production of T. V. sets in an industry for 7 days of a week:
| Day | Mon | Tue | Wed | Thurs | Fri | Sat | Sun |
| Number of T.V. Sets | 300 | 400 | 150 | 250 | 100 | 350 | 200 |
Represent the above information by a pictograph .
The following data gives the value (in crores of rupees) of the Indian export of cotton textiles for different years:
| Years | 1982 | 1983-1984 | 1984-1985 | 1985-1986 | 1986-1987 |
| Value of Export of Cotton Textiles (in crores of rupees) |
300 | 325 | 475 | 450 | 550 |
Represent the above data with the help of a bar graph. Indicate with the help of a bar graph the year in which the rate of increase in exports is maximum over the preceding year.
The following tables gives the quantity of goods (in crore tonnes)
| Year | 1950-51 | 1960-61 | 1965-66 | 1970-71 | 1980-81 | 1982-83 |
| Quantity of Goods (in crore tonnes) |
9 | 16 | 20 | 20 | 22 | 26 |
Explain through the bar graph if the quantity of goods carried by the Indian Railways in 1965-66 is more than double the quantity of goods carried in the year 1950-51.
The production of oil (in lakh tonnes) in some of the refineries in India during 1982 was given below:
| Refinery: | Barauni | Koyali | Mathura | Mumbai | Florida |
| Production of oil (in lakh tonnes) |
30 | 70 | 40 | 45 | 25 |
Construct a bar graph to represent the above data so that the bars are drawn horizontally.
In a histogram the class intervals or the group are taken along
A hundred students from a certain locality use different modes of travelling to school as given below. Draw a bar graph.
| Bus | Car | Rickshaw | Bicycle | Walk |
| 32 | 16 | 24 | 20 | 8 |
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.
Harmeet earns Rs.50 000 per month. He a budget for his salary as per the following table:
| Expenses | Accommodation | Food | Clothing | Travel | Miscellaneous | saving |
| Amount (Rs.) | 12000 | 9000 | 2500 | 7500 | 4000 | 15000 |
Draw a bar graph for the above data.
