Following are the marks scored by 30 students in a test out of 40 marks. Using tally marks prepare a frequency table:
30 |
18 |
27 |
15 |
25 |
28 |
15 |
30 |
35 |
36 |
25 |
30 |
20 |
28 |
17 |
30 |
36 |
35 |
35 |
18 |
30 |
17 |
30 |
|
25 |
36 |
28 |
25 |
25 |
18 |
16 |
30 |
39 |
58 |
17 |
34 |
50 |
23 |
37 |
42 |
49 |
55 |
59 |
19 |
28 |
47 |
49 |
18 |
60 |
56 |
36 |
58 |
35 |
55 |
37 |
25 |
34 |
39 |
61 |
53 |
33 |
36 |
53 |
61 |
62 |
39 |
53 |
21 |
18 |
28 |
23 |
Draw an appropriate graph to represent the given information.
To represent the given data by a bar-graph, draw two axes perpendicular to each other. Now, represent ‘Months’ on OX and ‘Number of watch sold’ on OY. Erect rectangles of the same width. The heights of the rectangles are proportional to number of watches, using a suitable scale:
Here, scale is 1 cm = 500 watches
Since 500 watches = 1 cm
1000 watches = 2 cm
1500 watches = 3 cm
2000 watches = 4 cm
2500 watches = 5 cm
(i) What is the size of the class intervals?
(ii) Which class has the highest frequency?
(iii) Which class has the lowest frequency?
(iv) What is the upper limit of the class interval 250-275?
(v) Which two classes have the same frequency?
40, |
38, |
33, |
48, |
60, |
53, |
31, |
46, |
34, |
36, |
49, |
41, |
55, |
49, |
65, |
42, |
44, |
47, |
38, |
39 |
(i) What information is being given by the histogram?
(ii) Which group contains maximum girls?
(iii) How many girls have a height of 145 cm and more?
(iv) If we divide the girls into the following three categories, how many would there be in each?
150 cm and more -Group A
140 cm to less than 150 cm -Group B
Less than 140 cm -Group C
For which of these would you use a histogram to show the data?
(a) The number of letters for different areas in a postman’ bag.
(b) The height of competitors in an athletics meet.
(c) The number of cassettes produced by 5 companies.
(d) The number of passengers boarding trains from 7:00 a.m. to 7:00 p.m. at a station.
Give reasons for each.