NCERT Solution for Class 8 Maths Chapter – 5 Data handling Exercise – 5.1
Q1. For which of these would you use a histogram to show the data ?
- The number of letters for different areas in a postman bag
- The height of competitors in an athletics meet.
- The number cassettes produced by 5 companies
- The number of passenger boarding trains from 7:00 AM to 7:00 PM at a station. Give reason for each
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Solution:-
We know that histogram is a graphical representation of data if the data represented using class – intervals
Since the cases mentioned in option (b) and (d) can be divided into class intervals, histogram can be used to show the data.
Similarly, since the cases mentioned in option (a) and ( c ) cannot be divided into class intervals, histogram cannot be used to represent the data.
Q2. 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 come during the first hour in the morning .
WWWWWWWWWWWWWWWWWWWWWWWWWWWWMMMMMMMMMMMMMMMBBBBBGGGGGGGGGGGG
Make a frequency distribution table using tally marks. Draw a bar graph to illustrate it.
Solution:-
Frequency distribution table:
Q3. The weekly wages ( in Rs) of 30 workers in a factory are:
830 , 835 , 890 , 810 , 835 , 836 , 869 , 845 , 898 , 820 , 860 , 832 , 833 , 855 , 845 , 804 , 808 , 812 , 840 , 885 , 835 , 836 , 878 , 840 , 868 , 890 , 806 , 840.
Using tally marks , male a frequency table with intervals as 800 – 810 , 810 – 820 and so on
Solution:-
The frequency table with intervals as 800 – 810 , 810 – 820 and so on, using tally mark is given below:
Q4. Draw a histogram for the frequency table made for the data in the question 3 and answer the following questions.
- Which group has the maximum numbers of workers ?
- How many workers earn Rs 850 and more?
- How many workers earn less than Rs 850?\
Solution:-
- 830 – 840 is the group having maximum numbers of workers ,9 compared to other groups
- Workers earning Rs 850 and more = 1 + 3 + 1 + 1 + 4 – 10
- Workers earning less than Rs 850 = 3 + 2 + 1 + 9 + 5 = 20
Q5. The number of hours for which students of a particular class watched television during holiday is shown through the given graph.
Answer the following:
- For how many hours did the maximum number of students watch T.V. ?
- How many students watched TV for less than 4 hours ?
- How many students spent more than 5 hours in watching TV ?
Solution:-
- 32 students watched T.V. for 4 – 5 hours The maximum number of students who watched T.V. for 4 – 5 hours.
- The number of students who watched T.V. less than 4 hours = 22 + 8 + 4 = 34
- The number of students who spent more than 5 hours in watching TV
= 8 + 6 = 14