Advertisements
Advertisements
Question
Draw a histogram for the frequency table made for the data in Question 3 and answer the following questions.
(1) Which group has the maximum number of workers?
(2) How many workers earn Rs 850 and more?
(3) How many workers earn less than Rs 850?
Advertisements
Solution
A histogram for the above frequency distribution table is as follows.

1) 830 − 840 is the group which has the maximum number of workers.
2) The workers who earn more than Rs 850 are the number of workers who fall in the group of 850 − 860 or 860 − 870 or 870 − 880 or 880 − 890. Hence, the total number of workers earning more than 850 will be the sum of the numbers of all these workers i.e., 1 + 3 + 1 + 1 + 4 = 10
3) The workers who earn less than Rs 850 are the number of workers who fall in the group of 800 − 810 or 810 − 820 or 820 − 830 or 830 − 840 or 840 − 850. Hence, the total number of workers earning less than 850 will be the sum of the numbers of all these workers i.e., 3 + 2 + 1 + 9 + 5 = 20
APPEARS IN
RELATED QUESTIONS
The marks scored by students in Mathematics in a certain Examination are given below:
| Marks Scored | Number of Students |
| 0 — 20 | 3 |
| 20 — 40 | 8 |
| 40 — 60 | 19 |
| 60 — 80 | 18 |
| 80 — 100 | 6 |
Draw histogram for the above data.
Find the correct answer from the alternatives given.
|
No. of trees planted by each student |
1 - 3 | 4 - 6 | 7 - 9 | 10 - 12 |
| No. of students | 7 | 8 | 6 | 4 |
The above data is to be shown by a frequency polygon. The coordinates of the points to show number of students in the class 4-6 are . . . .
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 |
| Number of schools: | 5 | 12 | 14 | 18 | 10 | 9 | 4 |
Draw a histogram to represent the following data:
| Monthly salary (in Rs) | Number of teachers |
| 5600−5700 | 8 |
| 5700−5800 | 4 |
| 5800−5900 | 3 |
| 5900−6000 | 5 |
| 6000−6100 | 2 |
| 6100−6200 | 3 |
| 6200−6300 | 1 |
| 6300−6400 | 2 |
The following frequency distribution table shows marks obtained by 180 students in Mathematics examination.
| Marks | No. of students |
| 0 - 10 | 25 |
| 10 - 20 | x |
| 20 - 30 | 30 |
| 30 - 40 | 2x |
| 40 - 50 | 65 |
Find the value of x. Also draw a histogram representing the above information.
Find the lower quartile, the upper quartile, the interquartile range and the semi-interquartile range for the following frequency distributions:
| Variate | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 |
| Frequency | 1 | 2 | 3 | 1 | 2 | 4 | 2 | 1 | 1 | 2 | 1 |
Construct histograms for following frequency distribution:
| Class Interval | 0-10 | 10-20 | 20-30 | 30-40 | 40-50 | 50-60 |
| Frequency | 8 | 20 | 34 | 22 | 10 | 6 |
Construct a frequency polygon without using a histogram for the following frequency distribution :
| Class Interval | 10-20 | 20-40 | 40-60 | 60-80 | 80-100 |
| Frequency | 9 | 17 | 15 | 20 | 14 |
Represent the following data by histogram:
| Price of sugar Per kg (in Rs) | Number of weeks |
| 28-30 | 4 |
| 30-32 | 8 |
| 32-34 | 22 |
| 34-36 | 12 |
| 36-38 | 6 |
Draw histogram and hence the frequency polygon for the following frequency distribution:
| Rainfall (in cm) | No. of years |
| 20-25 | 2 |
| 25-30 | 5 |
| 30-35 | 8 |
| 35-40 | 12 |
| 40-45 | 10 |
| 45-50 | 7 |
The marks scored by students in Mathematics in a certain examination are given below :
| Marks Scored | Number of Students |
| 0 - 20 | 6 |
| 20 - 40 | 9 |
| 40 - 60 | 14 |
| 60 - 80 | 16 |
| 80 - 100 | 5 |
Draw histogram for the above data.
Distribution of height in cm of 100 people is given below:
| Class interval (cm) | Frequency |
| 145 - 155 | 3 |
| 155 - 165 | 35 |
| 165 - 175 | 25 |
| 175 - 185 | 15 |
| 185 - 195 | 20 |
| 195 - 205 | 2 |
Draw a histogram to represent the above data.
Form a continuous frequency distribution table and draw histogram from the following data.
| Age (in years) | No. of persons |
| Under 5 | 1 |
| Under 10 | 12 |
| Under 15 | 19 |
| Under 20 | 26 |
| Under 25 | 27 |
| Under 30 | 35 |
| Under 35 | 38 |
| Under 40 | 45 |
| Under 45 | 48 |
| Under 50 | 53 |
Try yourself
- Next time when you watch your favourite TV programme, count the number of advertisements during each break. Use tally marks. Put a dot below the tally when you find children in any advertisement.
- Compare with your friends. Do you get different answers?
Histogram shows the number of people owning the different number of books. Answer the question based on it.

The number of people owning books less than 40 is ______.
Histogram shows the number of people owning the different number of books. Answer the question based on it.

The number of people having books more than 20 and less than 40 is ______.
In a histogram ______ are drawn with width equal to a class interval without leaving any gap in between.
Look at the histogram below and answer the questions that follow.

- How many students have height more than or equal to 135 cm but less than 150 cm?
- Which class interval has the least number of students?
- What is the class size?
- How many students have height less than 140 cm?
Draw a histogram to represent the frequency distribution in question 91.
The given graph with a histogram represents the number of plants of different heights grown in a school campus. Study the graph carefully and answer the following questions:

- Make a frequency table with respect to the class boundaries and their corresponding frequencies.
- State the modal class.
- Identify and note down the mode of the distribution.
- Find the number of plants whose height range is between 80 cm to 90 cm.
