Properties of Rational Numbers

IMPORTANT

Important Questions on Properties of Rational Numbers

MEDIUM
IMPORTANT

75×-310+75×910 Find using distributive property.

EASY
IMPORTANT

916×3+916×-19 Find using distributive property.

EASY
IMPORTANT

Check whether it is a rational number.

-23÷611=_____.

EASY
IMPORTANT

Check whether it is a rational number.

21×1913=_____.

EASY
IMPORTANT

Check whether it is a rational number.

37×52=_____.

EASY
IMPORTANT

Check whether it is a rational number.

489-118=_____.

EASY
IMPORTANT

Check whether it is a rational number.

23-37=_____.

EASY
IMPORTANT

Check whether it is a rational number.

72+27=_____.

MEDIUM
IMPORTANT

Fill in the following blanks.

3×_____=3 and _____×3=3

-2×_____=-2 and _____×-2=-2

78×_____=78 and _____×78=78

What observations have you made in the above multiplications?

MEDIUM
IMPORTANT

Complete the following table.

Numbers Associative under
Addition Subtraction Multiplication Division
Natural numbers Yes      
Whole numbers       No
Integers   Yes    
Rational Numbers     Yes  

MEDIUM
IMPORTANT

Complete the table with necessary illustrations and remarks for integers.

Operation Integers with example Remark
Addition

Is 2+[(-3)+5)]=[(2+(-3)]+5?

2+[(-3)+5]=2+[-3+5]=2+2=4

 [2+(-3)]+5=[2-3]+5=-1+5=4

For any three integers a, b, c

a+(b+c)=(a+b)+c

 
Subtraction

Is 6-(9-5)=(6-9)-5?

 
Multiplication Is 2×[7×(-3)]=(2×7)×(-3)?  
Division

10÷ [2÷(-5)]=[10÷2]÷(-5)?

10÷2÷-5=10÷2-5=10×-52=-25

Now, 10÷2÷-5=102÷-5=5÷-5=5-5=-1

Thus, 10÷ [2÷(-5)][10÷2]÷(-5)

 

MEDIUM
IMPORTANT

Complete the table with necessary illustrations and remarks for whole numbers.

Operation Examples with whole numbers Remark
Addition

Is 2+(3+0)=(2+3)+0?

2+(3+0)=2+3=5

(2+3)+0=5+0=5

2+(3+0)=(2+3)+0

a+(b+c)=(a+b)+c

for any three whole numbers a, b, c

 
Subtraction

(2-3)-2=? 2-(3-2)=?  

Is (2-3)-2=2-(3-2)?

Subtraction is not associative
Multiplication   Multiplication is associative
Division

Is 2÷(3÷5)=(2÷3)÷5?

2÷3÷5=2÷35=2×53=103

2÷3÷5=23÷5=23×15=215

2÷3÷52÷3÷5

Division is not associative

MEDIUM
IMPORTANT

Complete the following table.

Numbers Commutative with respect to
Addition Subtraction Multiplication Division
Natural numbers Yes No Yes  
Whole numbers       No
Integers        
Rational Numbers       No

MEDIUM
IMPORTANT

Complete the following table for integers.

Operation Example Remark
Addition   Addition is commutative in Integers.
Subtraction 2, 3 are integers 2-(3)=? (3)-2=? Is 2- 3)=(3)-2=?  
Multiplication    
Division   Division is not Commutative in Integers

EASY
IMPORTANT

Complete the following table for whole numbers.

Operation Example Remark
Addition 2, 3 are whole numbers 2+3=5 and 3+2=52+3=3+2 Addition is commutative in W.
Subtraction Is 3-2 equal to 2-3? Subtraction is not commutative
Multiplication    
Division 4÷2=? 2÷4=? Is  4÷2=2÷4?  

EASY
IMPORTANT

Fill the blanks in the table.

Numbers Closure property under
Addition Subtraction Multiplication Division
Natural numbers Yes      
Whole numbers       No
Integers   Yes    
Rational Numbers     Yes  

EASY
IMPORTANT

If we exclude zero from the set of integers is it closed under division? Check the same for natural numbers.

MEDIUM
IMPORTANT

The product of the rational numbers, 3÷1713=_____.

EASY
IMPORTANT

Check whether it is a rational number.

0+12=_____.

MEDIUM
IMPORTANT

The product of the rational numbers, -23÷611=_____.