class 9 math ncert solution answer key EXERCISE math 1.1

QUESTION 1. Is zero a rational number? can you write it in the form , where  and  are integers and  ?
SOLUTION. Yes, zero is a rational number. It can be written as , etc., where denominator , it can be negative also.

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QUESTION 2. Find six rational numbers between 3 and 4.
SOLUTION.

S.No.	Numbers	Mid value
1	3 and 4
2	3 and
3	and
4	4 and
5	and
6	and

Hence 6 rational numbers between 3 and 4 are

QUESTION 3. Find five rational numbers between  and .
SOLUTION. Since we want to find out 5 numbers between  and , so we multiply the numerator and denominator of  and  by , i.e., 6 .

Hence, five rational numbers between  and  are  and .
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QUESTION 4. Are the following statements true or false? Give reasons for your answer.
(i) Every natural number is a whole number.
(ii) Every integer is a whole number.
(iii) Every rational number is a whole number.

SOLUTION. (i) True, since natural number starts from 1 to  and whole number starts from 0 to .
(ii) False, since negative integers are not whole numbers.
(iii) False, since rational number such that  is not whole number.