For which of these would you use a histogram to show the data?
(a) The number of letters for different areas in a postman’s 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.
Solution:
A histogram can be defined as a set of rectangles with bases along with the intervals between class boundaries. Each rectangle bar depicts some sort of data and all the rectangles are adjacent. It is the graphical representation of data where data is grouped into continuous number ranges and each range corresponds to a vertical bar.
(a) The number of areas cannot be represented in terms of class interval. So, we cannot use the histogram to show the data.
(b) Height of competitors can be divided into intervals. So, we can use a histogram here.
For example,
Height in (cm) | Number of competitors |
150-160 160-170 170-180 180-190 |
10 12 5 2 |
(c) Companies cannot be divided into class intervals. So, we cannot use a histogram here.
(d) Time for boarding the train can be divided into intervals. So, we can use a histogram here.
For example,
Time in hours | Number of passengers |
7 am – 10 am 10 am – 1 pm 1 pm – 4 pm 4 pm – 7 pm |
1500 2000 1000 800 |
We can use a histogram for cases (b) and (d) as they can be divided into class intervals.
☛ Check: NCERT Solutions for Class 8 Maths Chapter 5
Video Solution:
For which of these would you use a histogram to show the data? (a) The number of letters for different areas in a postman’s 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
NCERT Solutions for Class 8 Maths Chapter 5 Exercise 5.1 Question 1
Summary:
We can use a histogram for cases (b) The height of competitors in an athletics meet and (d) The number of passengers boarding trains from 7:00 a.m. to 7:00 p.m. at a station. as they can be divided into class intervals whereas (a) The number of letters for different areas in a postman’s bag and (c) The number of cassettes produced by 5 companies cannot be represented in form of histograms as they cannot be divided into class intervals.
☛ Related Questions:
- The shoppers who come to a departmental store are marked as: man (M), woman (W), boy (B) or girl (G). The following list gives the shoppers who came during the first hour in the morning: W W W G B W W M G G M M W W W W G B M W B G G M W W M M W W W M W B W G M W W W W G W M M W W M W G W M G W M M B G G W Make a frequency distribution table using tally marks. Draw a bar grapha to illustrate it.
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- The number of hours for which students of a particular class watched television during holidays is shown through the given graph. Answer the following: (i) For how many hours did the maximum number of students watch T.V.? (ii) How many students watched T.V. for less than 4 hours? (iii) How many students spent more than 5 hours in watching T.V.?
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