**Chapter
1 Rational Numbers**

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**Exercise 1.1**

**Ex 1.1 Class 8 Maths
Question 1.
Using appropriate properties find:**

Solution:

Solution:

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** **

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**Ex 1.1 **

**Question 2.
Write the additive inverse of each of the following:**

(i)

(ii)

(iii)

(iv)

(v)

Solution:

(i)

(ii)

(iii)

(iv)

(v)

Solution:

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**Question 3.
Verify that -(-x) = x for
(i) x = **

(ii) x =

(ii) x =

Solution:

Solution:

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** **

** **

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**Question 4.**

**
Find the multiplicative inverse of the following:
**

Solution:

Solution:

**Ex 1.1 Class 8 Maths
Question 5.
Name the property under multiplication used in each of the following:**

Solution:

(i) Commutative property of multiplication

(ii) Commutative property of multiplication

(iii) Multiplicative inverse property

Solution:

(i) Commutative property of multiplication

(ii) Commutative property of multiplication

(iii) Multiplicative inverse property

**Ex 1.1 Class 8 Maths **

**Question 6.
Multiply **

**by the reciprocal of**

**.**

Solution:

Solution:

** **

**Ex 1.1 Class 8 Maths **

**Question 7.
Tell what property allows you to compute**

Solution:

Since a × (b × c) = (a × b) × c shows the associative property of multiplications.

Solution:

Since a × (b × c) = (a × b) × c shows the associative property of multiplications.

**Ex 1.1 Class 8 Maths **

**Question 8.
Is
**

** **

**Ex 1.1 Class 8 Maths **

**Question 9.
If 0.3 the multiplicative inverse of 3**

**? Why or why not?**

Solution:

Solution:

Multiplicative inverse of 0.3 or
is
.

Thus, 0.3 is the multiplicative inverse of 3
.

Multiplicative inverse of 0.3 or

Thus, 0.3 is the multiplicative inverse of 3

**Ex 1.1 Class 8 Maths **

**Question 10.
Write:
(i) The rational number that does not have a reciprocal.
(ii) The rational numbers that are equal to their reciprocals.
(iii) The rational number that is equal to its negative.**

Solution:

(i) 0 is the rational number which does not have its reciprocal

[

Solution:

(i) 0 is the rational number which does not have its reciprocal

[

**∵**

is not defined]

(ii) Reciprocal of 1 =
= 1

Reciprocal of -1 =
= -1

Thus, 1 and -1 are the required rational numbers.

(iii) 0 is the rational number which is equal to its negative.

(ii) Reciprocal of 1 =

Reciprocal of -1 =

Thus, 1 and -1 are the required rational numbers.

(iii) 0 is the rational number which is equal to its negative.

**Ex 1.1 Class 8 Maths **

**Question 11.**

Fill in the blanks.

(i) Zero has ……….. reciprocal.

(ii) The numbers ……….. and ……….. are their own reciprocals.

(iii) The reciprocal of -5 is ………

(iv) Reciprocal of
, where x ≠ 0 is ……….

(v) The product of two rational numbers is always a …………

(vi) The reciprocal of a positive rational number is ……….

Solution:

(i) no

(ii) -1 and 1

(iii)

(iv) x

(v) rational number

(vi) positive

Fill in the blanks.

(i) Zero has ……….. reciprocal.

(ii) The numbers ……….. and ……….. are their own reciprocals.

(iii) The reciprocal of -5 is ………

(iv) Reciprocal of

(v) The product of two rational numbers is always a …………

(vi) The reciprocal of a positive rational number is ……….

Solution:

(i) no

(ii) -1 and 1

(iii)

(iv) x

(v) rational number

(vi) positive

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