Advertisements
Advertisements
Question
In a public library, the following observations were recorded by the librarian in a particular week:
| Days | Mon | Tues | Wed | Thurs | Fri | Sat |
| Newspaper Readers |
400 | 600 | 350 | 550 | 500 | 350 |
| Magazines Readers |
150 | 100 | 200 | 300 | 250 | 200 |
- Draw a double bar graph choosing an appropriate scale.
- On which day, the number of readers in the library was maximum?
- What is the mean number of magazine readers?
Advertisements
Solution
a. Steps to construct the bar graphs are as follows:
Step I: We draw two lines perpendicular to each other on graph paper and call them horizontal and vertical axes.
Step II: Along the horizontal axis, we mark the days and along the vertical axis, we mark the readers.
Step III: We choose a suitable scale to determine the heights of bars. Here, we choose the scale as 1 small division to represent 50.
Step IV: First, we draw the bars for newspaper readers and then bars for magazine readers for different days.
Bars for newspapers and magazine readers are shaded separately and the shading is shown in the top right corner of the graph paper.
b. Total number of both readers in different days are
| Day | Readers |
| Mon | 400 + 150 = 550 |
| Tue | 600 + 100 = 700 |
| Wed | 350 + 200 = 550 |
| Thur | 550 + 300 = 850 |
| Fri | 500 + 250 = 750 |
| Sat | 350 + 200 = 550 |
Hence, it is clear that the number of readers was maximum on Thursday.
c. Mean of readers = `"Sum of all the magazine readers on six days"/6`
= `(150 + 100 + 200 + 300 + 250 + 200)/6`
= `1200/6`
= 200
APPEARS IN
RELATED QUESTIONS
In the table given below, the information is given about roads. Using this draw a sub-divided and percentage bar diagram (Approximate the percentages to the nearest integer).
| Year | Permanent Roads ( Lakh km.) |
Temporary Roads ( Lakh km.) |
| 2000-2001 | 14 | 10 |
| 2001-2002 | 15 | 11 |
| 2002-2003 | 17 | 13 |
| 2003-2004 | 20 | 19 |
The following table shows the number of Buses and Trucks in nearest lakh units. Draw percentage bar-diagram. (Approximate the percentages to the nearest integer)
| Year | No. of Trucks | No. of Buses |
| 2005-2006 | 47 | 9 |
| 2007-2008 | 56 | 13 |
| 2008-2009 | 60 | 16 |
| 2009-2010 | 63 | 18 |
Practice time: Afterschool
Ask 10 of your friends about what they like to do most after school.
| What they like to do after school |
Number of children |
| Watching TV | |
| Playing football | |
| Reading storybooks | |
The graph given below gives the actual and expected sales of cars of a company for 6 months. Study the graph and answer the questions that follow.
- In which month was the actual sales same as the expected sales?
- For which month(s) was (were) the difference in actual and expected sales the maximum?
- For which month(s) was (were) the difference in actual and expected sales the least?
- What was the total sales of cars in the months–Jan, Feb. and March?
- What is the average sales of cars in the last three months?
- Find the ratio of sales in the first three months to the last three months
The following bar graph shows the number of houses (out of 100) in a town using different types of fuels for cooking.
Read the bar graph and answer the following questions:
Scale: 1 unit length = 5 houses
- Which fuel is used in maximum number of houses?
- How many houses are using coal as fuel?
- Suppose that the total number of houses in the town is 1 lakh.
From the above graph estimate the number of houses using electricity.
The bar graph given below shows the marks of students of a class in a particular subject:
Study the bar graph and answer the following questions:
- If 40 is the pass mark, then how many students have failed?
- How many students got marks from 50 to 69?
- How many students scored 90 marks and above?
- If students who scored marks above 80 are given merits then how many merit holders are there?
- What is the strength of the class?
The bar graph given below represents the circulation of newspapers (dailies) in a town in six languages (the figures are approximated to hundreds).
Study the bar graph and answer the following questions:
- Find the total number of newspapers read in Hindi, Punjabi, Urdu, Marathi and Tamil.
- Find the excess number of newspapers read in Hindi than those in English.
- Name the language in which the least number of newspapers are read.
- Write the total circulation of newspapers in the town.
Observe the given data:
| Days of the week |
Mon | Tues | Wed | Thurs | Fri | Sat |
| Number of Mobile Phone Sets Sold |
50 | 45 | 30 | 55 | 27 | 60 |
- Draw a bar graph to represent the above given information.
- On which day of the week was the sales maximum?
- Find the total sales during the week.
- Find the ratio of the minimum sale to the maximum sale.
- Calculate the average sale during the week.
- On how many days of the week was the sale above the average sales?
The students of Class VII have to choose one club from Music, Dance, Yoga, Dramatics, Fine arts and Electronics clubs. The data given below shows the choices made by girls and boys of the class. Study the table and answer the questions that follow:
| Clubs | Music | Dance | Yoga | Dramatics | Fine Arts | Electronics |
| Girls | 15 | 24 | 10 | 19 | 27 | 21 |
| Boys | 12 | 16 | 8 | 17 | 11 | 30 |
- Draw a double bar graph using appropriate scale to depict the above data.
- How many students are there in Class VII?
- Which is the most preferred club by boys?
- Which is the least preferred club by girls?
- For which club the difference between boys and girls is the least?
- For which club is the difference between boys and girls the maximum?
The table below compares the population (in hundreds) of 4 towns over two years:
| Towns | A | B | C | D |
| 2007 | 2900 | 6400 | 8300 | 4600 |
| 2009 | 3200 | 7500 | 9200 | 6300 |
Study the table and answer the following questions:
- Draw a double bar graph using appropriate scale to depict the above information.
- In which town was the population growth maximum?
- In which town was the population growth least?
