Page 110 - Ganit Kaushal

Ex. A teacher, Nand Kishor, collected responses from the children of his middle school in Delhi regarding
how often they slept at least 9 hours during the night. He prepared a pictograph from the data: (NCERT)
Answer the following questions using the pictograph:
(a) What is the number of children who always Response Number of Children ( = 10 Children)
slept at least 9 hours at night? Always
(b) How many children sometimes slept at least 9 Sometimes
hours at night? Never
(c) How many children always slept less than 9 hours each night? Explain how you got your answer.
Observe that, here the key is ( = 10 Children)
Sol. (a) In the table, there are 5 pictures for ‘Always’. Each picture represents 10 children. Therefore,
5 × 10 = 50 children who always slept at least 9 hours at night.
(b) There are 2 complete pictures (2 × 10 = 20) and a half picture (half of 10 = 5). Therefore, the
number of children who sometimes slept at least 9 hours is 20 + 5 = 25.

(c) There are 4 complete pictures for ‘Never’. Hence, 4 × 10 = 40 children never sleep at least 9 hours
a night, i.e., they always sleep less than 9 hours.

Solved Examples

Ex 1. Look at the following pictograph Modes of Travelling Number of Students = 1 Student
that helps you understand at a glance
the different modes of travel used by Private car
students. Based on this picture, answer Public bus
the following questions: (NCERT) School bus
(a) Which mode of travel is used by the Cycle
greatest number of students? Walking
(b) Which mode of travel is used by the
least number of students?

Sol. (a) Here, the number of symbols for school bus is the maximum. Therefore, the school bus is used as
a mode of travel by the greatest number of students.
(b) The number of symbols for cycle is the minimum. So, the cycle is used as a mode of travel by the
least number of students.
Ex 2. One day, Lakhanpal collected data on how many students were absent in each class and wrote it as in
the following table. (NCERT)
Class I II III IV V VI VII VIII
No. of students 3 5 4 2 0 1 5 7

He created a pictograph to present this data and decided to show = 1 Student
1 student as in the pictograph. VIII
Based on this picture, answer the following questions: VII
(a) Which class has the maximum number of absentees? VI
(b) Which class has no absentees? Classes V
(c) What is the maximum number of absentees in any of the classes? IV
Sol. (a) Class-VIII has the maximum number of absentees. III
(b) Class-V has no absentees. II
(c) The maximum number of absentees is 7 in class-VIII. I
No. of students absent

108 Mathematics-6