Exercise 4.1
Q1
- A survey was made to find the type of music that a certain group of young people liked in a city. Adjoining pie chart shows the findings of this survey.
From this pie chart answer the following:
(i) If 20 people liked classical music, how many young people were surveyed?
(ii) Which type of music is liked by the maximum number of people?
(iii) If a cassette company were to make 1000 CD’s, how many of each type would they make?
Sol
Solution:
(i) If we say that 10 % represents 100 people, we get: 20% represents
Thus, 200 people were surveyed.
(ii) Since
(iii) CDs of classical music =
CDs of semi-classical music =
CDs of light music =
CDs of folk music =
- A group of 360 people were asked to vote for their favourite season from the three seasons rainy, winter and summer.
(i) Which season got the most votes?
(ii) Find the central angle of each sector.
(iii) Draw a pie chart to show this information.
| Season | No. of Votes |
|---|---|
| Summer | 90 |
| Rainy | 120 |
| Winter | 150 |
Solution:
(i) According to the table given in the question, the
(ii) Central angle of summer season =
Central angle of rainy season =
Central angle of winter season =
- Draw a pie chart showing the following information. The table shows the colours preferred by a group of people.
| Colours | No. of people |
|---|---|
| Blue | 18 |
| Green | 9 |
| Red | 6 |
| Yellow | 3 |
| Total | 36 |
Solution:
Here, central angle = 360° Total number of people = 36
| Colours | No. of people | In fractions | Central Angles |
|---|---|---|---|
| Blue | 18 | ||
| Green | 9 | ||
| Red | 6 | ||
| Yellow | 3 |
- The adjoining pie chart gives the marks scored in an examination by a student in Hindi, English, Mathematics, Social Science and Science. If the total marks obtained by the students were 540, answer the following questions.
(i) In which subject did the student score 105 marks ? (Hint: for 540 marks, the central angle = 360°. So, for 105 marks, what is the central angle?)
(ii) How many more marks were obtained by the student in Mathematics than in Hindi?
(iii) Examine whether the sum of the marks obtained in Social Science and Mathematics is more than that in Science and Hindi. (Hint: Just study the central angles).
| Subjects | Central Angles | Marks Obtained |
|---|---|---|
| Hindi | 70° | |
| English | 55° | |
| Maths | 90° | |
| Science | 80° | |
| S. Science | 65° |
(i) From the table, we can see that in
(ii) From the table, we can see that the student scored more in Mathematics than in Hindi by a margin of
(iii)
- The number of students in a hostel, speaking different languages is given below. Display the data in a pie chart.
| Languages | No. of students |
|---|---|
| Hindi | 40 |
| English | 12 |
| Marathi | 9 |
| Tamil | 7 |
| Bengali | 4 |
| Total | 72 |
| Languages | No. of students | In fractions | Central Angles |
|---|---|---|---|
| Hindi | 40 | ||
| English | 12 | ||
| Marathi | 9 | ||
| Tamil | 7 | ||
| Bengali | 4 |