In this Exercise 1.1 of the class 9 maths , we discuss about some basic and definition based problems.
Exercise 1.1 Class 9 Maths
Rational Number-
A number which is written in the form of P/q form,where p and q are integer and q≠0
Every Integer is a rational number but every rational number is not a Integer.
Question 1 – Is zero is a rational number ?can you write it in the form of p/q where p and q are integer and q≠0 ?
Answer : Yes! zero is a rational number, because it can be written as 0/1,0/2 ,0/3 …. which is form of p/q where q≠0
Question 2 : Find six rational number between 3 and 4 ?
Answer 2: There are many rational number between 3 and 4
(3+4)/2 = 7/2 =3.5
3.55 , 3.60 3.65 3.70 3.75
Thus we have six rational number ( 3.50,3.55, 3.60, 3.65, 3.70, 3.75 )
Question 3
Find five rational number between 3/5 and 4/5 ?
Answer :
3/5= 0.6 and 4/5 = 0.8
So we have find rational number between 0.6 and 0.8
There are many rational number between 0.6 and 0.8, some of them is given below.
i.e. 0.62, 0.65, 0.68, 0.70,0.72, 0.75
Question 4:
State whether the following statement are true or false? Give reason for your Answer.
(1)-Every natural number is a whole number?
True ! Because whole number is a collection of zero and natural number.
(2)-Every integer is a whole number ?
False! Because negative integer is not a whole number.
(3)-Every rational number is a whole number ?
False ! Because rational number is 2/3 ,3/4 ..etc which is not a whole number.
Example of exercise 1.1 class 9 maths :
Are the following statements true or false? Give reason for your answer.
(i) Every whole number is a natural number.
(ii) Every integer is a rational number.
(iii) Every rational number is an integer.
Answer :
(i) False, because zero is a whole number but not a natural number.
(ii) True, because integer m can be expressed in the form of m/l , and so, it is a rational number.
(iii) False , because 3/5 is not an integer.