Scroll:Real Number System >> Rational Numbers ( Exercise 1.1) >> saq (4363)


Written Instructions:

For each Multiple Choice Question (MCQ), four options are given. One of them is the correct answer. Make your choice (1,2,3 or 4). Write your answers in the brackets provided..

For each Short Answer Question(SAQ) and Long Answer Question(LAQ), write your answers in the blanks provided.

Leave your answers in the simplest form or correct to two decimal places.



 

1)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

12 , 44 and -27

RHS =


Answer:_______________




2)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

12 , 44 and -25

RHS =


Answer:_______________




3)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

34 , 26 and -45

RHS =


Answer:_______________




4)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

23 , 36 and -25

RHS =


Answer:_______________




5)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

34 , 56 and -35

RHS =


Answer:_______________




6)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

32 , 55 and -37

RHS =


Answer:_______________




7)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

12 , 26 and -27

RHS =


Answer:_______________




8)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

33 , 45 and -26

RHS =


Answer:_______________




9)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

24 , 26 and -25

RHS =


Answer:_______________




10)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

24 , 54 and -27

RHS =


Answer:_______________




 

1)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

12 , 44 and -27

RHS = Answer: 1714


SOLUTION 1 :

To verify,

( 12 + 44 ) + ( -27 )  =   12 + ( 44 + ( -27 )

LHS

1
+
 
4
+
 
-2 = 1x4 + 4x2 + -2
2 4 7 2x4 4x2 7

 

[ LCM of 2 and 4 is 8]

 

4
+
 
8 + -2
8 8 7

 

4+8
+
 
-2  = 12 -2 12 2
7 8 7 8 7

 

[LCM of 8 ans 7 is 56]

12x7
-
 
2x8 = 84 - 16 = 84- 16 = 68 = 1714
8x7 7x8 56 56 56 56

 

LHS = 1714

 

RHS   12 + ( 44 + ( -27 )  =   12 + ( 44 -27 )

1
+
 
4x7 - 2x4
2 4x7 7x4

 

[LCM of 4 and 7 is 28]

1
+
 
28 - 8 = 1

+

28-8 = 1 + 20
2 28 28 2 28 2 28

 

[LCM of 2 and 28 is 56]

 

1x28
+
 
20x2 = 28 + 40 = 28+(40) = 68 = 1714
2x28 28x2 56 56 56 56

 

RHS = 1714

LHS = RHS

Hence, associative property is true for addition.



2)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

12 , 44 and -25

RHS = Answer: 1110


SOLUTION 1 :

To verify,

( 12 + 44 ) + ( -25 )  =   12 + ( 44 + ( -25 )

LHS

1
+
 
4
+
 
-2 = 1x4 + 4x2 + -2
2 4 5 2x4 4x2 5

 

[ LCM of 2 and 4 is 8]

 

4
+
 
8 + -2
8 8 5

 

4+8
+
 
-2  = 12 -2 12 2
5 8 5 8 5

 

[LCM of 8 ans 5 is 40]

12x5
-
 
2x8 = 60 - 16 = 60- 16 = 44 = 1110
8x5 5x8 40 40 40 40

 

LHS = 1110

 

RHS   12 + ( 44 + ( -25 )  =   12 + ( 44 -25 )

1
+
 
4x5 - 2x4
2 4x5 5x4

 

[LCM of 4 and 5 is 20]

1
+
 
20 - 8 = 1

+

20-8 = 1 + 12
2 20 20 2 20 2 20

 

[LCM of 2 and 20 is 40]

 

1x20
+
 
12x2 = 20 + 24 = 20+(24) = 44 = 1110
2x20 20x2 40 40 40 40

 

RHS = 1110

LHS = RHS

Hence, associative property is true for addition.



3)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

34 , 26 and -45

RHS = Answer: 1760


SOLUTION 1 :

To verify,

( 34 + 26 ) + ( -45 )  =   34 + ( 26 + ( -45 )

LHS

3
+
 
2
+
 
-4 = 3x6 + 2x4 + -4
4 6 5 4x6 6x4 5

 

[ LCM of 4 and 6 is 24]

 

18
+
 
8 + -4
24 24 5

 

18+8
+
 
-4  = 26 -4 26 4
24  5 24 5 24 5

 

[LCM of 24 ans 5 is 120]

26x5
-
 
4x24 = 130 - 96 = 130- 96 = 34 = 1760
24x5 5x24 120 120 120 120

 

LHS = 1760

 

RHS   34 + ( 26 + ( -45 )  =   34 + ( 26 -45 )

3
+
 
2x5 - 4x6
4 6x5 5x6

 

[LCM of 6 and 5 is 30]

3
+
 
10 - 24 = 3

+

10-24 = 3 + -14
4 30 30 4 30 4 30

 

[LCM of 4 and 30 is 120]

 

3x30
+
 
-14x4 = 90 + -56 = 90+(-56) = 34 = 1760
4x30 30x4 120 120 120 120

 

RHS = 1760

LHS = RHS

Hence, associative property is true for addition.



4)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

23 , 36 and -25

RHS = Answer: 2330


SOLUTION 1 :

To verify,

( 23 + 36 ) + ( -25 )  =   23 + ( 36 + ( -25 )

LHS

2
+
 
3
+
 
-2 = 2x6 + 3x3 + -2
3 6 5 3x6 6x3 5

 

[ LCM of 3 and 6 is 18]

 

12
+
 
9 + -2
18 18 5

 

12+9
+
 
-2  = 21 -2 21 2
18  5 18 5 18 5

 

[LCM of 18 ans 5 is 90]

21x5
-
 
2x18 = 105 - 36 = 105- 36 = 69 = 2330
18x5 5x18 90 90 90 90

 

LHS = 2330

 

RHS   23 + ( 36 + ( -25 )  =   23 + ( 36 -25 )

2
+
 
3x5 - 2x6
3 6x5 5x6

 

[LCM of 6 and 5 is 30]

2
+
 
15 - 12 = 2

+

15-12 = 2 + 3
3 30 30 3 30 3 30

 

[LCM of 3 and 30 is 90]

 

2x30
+
 
3x3 = 60 + 9 = 60+(9) = 69 = 2330
3x30 30x3 90 90 90 90

 

RHS = 2330

LHS = RHS

Hence, associative property is true for addition.



5)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

34 , 56 and -35

RHS = Answer: 5960


SOLUTION 1 :

To verify,

( 34 + 56 ) + ( -35 )  =   34 + ( 56 + ( -35 )

LHS

3
+
 
5
+
 
-3 = 3x6 + 5x4 + -3
4 6 5 4x6 6x4 5

 

[ LCM of 4 and 6 is 24]

 

18
+
 
20 + -3
24 24 5

 

18+20
+
 
-3  = 38 -3 38 3
24  5 24 5 24 5

 

[LCM of 24 ans 5 is 120]

38x5
-
 
3x24 = 190 - 72 = 190- 72 = 118 = 5960
24x5 5x24 120 120 120 120

 

LHS = 5960

 

RHS   34 + ( 56 + ( -35 )  =   34 + ( 56 -35 )

3
+
 
5x5 - 3x6
4 6x5 5x6

 

[LCM of 6 and 5 is 30]

3
+
 
25 - 18 = 3

+

25-18 = 3 + 7
4 30 30 4 30 4 30

 

[LCM of 4 and 30 is 120]

 

3x30
+
 
7x4 = 90 + 28 = 90+(28) = 118 = 5960
4x30 30x4 120 120 120 120

 

RHS = 5960

LHS = RHS

Hence, associative property is true for addition.



6)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

32 , 55 and -37

RHS = Answer: 2914


SOLUTION 1 :

To verify,

( 32 + 55 ) + ( -37 )  =   32 + ( 55 + ( -37 )

LHS

3
+
 
5
+
 
-3 = 3x5 + 5x2 + -3
2 5 7 2x5 5x2 7

 

[ LCM of 2 and 5 is 10]

 

15
+
 
10 + -3
10 10 7

 

15+10
+
 
-3  = 25 -3 25 3
10  7 10 7 10 7

 

[LCM of 10 ans 7 is 70]

25x7
-
 
3x10 = 175 - 30 = 175- 30 = 145 = 2914
10x7 7x10 70 70 70 70

 

LHS = 2914

 

RHS   32 + ( 55 + ( -37 )  =   32 + ( 55 -37 )

3
+
 
5x7 - 3x5
2 5x7 7x5

 

[LCM of 5 and 7 is 35]

3
+
 
35 - 15 = 3

+

35-15 = 3 + 20
2 35 35 2 35 2 35

 

[LCM of 2 and 35 is 70]

 

3x35
+
 
20x2 = 105 + 40 = 105+(40) = 145 = 2914
2x35 35x2 70 70 70 70

 

RHS = 2914

LHS = RHS

Hence, associative property is true for addition.



7)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

12 , 26 and -27

RHS = Answer: 2342


SOLUTION 1 :

To verify,

( 12 + 26 ) + ( -27 )  =   12 + ( 26 + ( -27 )

LHS

1
+
 
2
+
 
-2 = 1x6 + 2x2 + -2
2 6 7 2x6 6x2 7

 

[ LCM of 2 and 6 is 12]

 

6
+
 
4 + -2
12 12 7

 

6+4
+
 
-2  = 10 -2 10 2
12  7 12 7 12 7

 

[LCM of 12 ans 7 is 84]

10x7
-
 
2x12 = 70 - 24 = 70- 24 = 46 = 2342
12x7 7x12 84 84 84 84

 

LHS = 2342

 

RHS   12 + ( 26 + ( -27 )  =   12 + ( 26 -27 )

1
+
 
2x7 - 2x6
2 6x7 7x6

 

[LCM of 6 and 7 is 42]

1
+
 
14 - 12 = 1

+

14-12 = 1 + 2
2 42 42 2 42 2 42

 

[LCM of 2 and 42 is 84]

 

1x42
+
 
2x2 = 42 + 4 = 42+(4) = 46 = 2342
2x42 42x2 84 84 84 84

 

RHS = 2342

LHS = RHS

Hence, associative property is true for addition.



8)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

33 , 45 and -26

RHS = Answer: 2215


SOLUTION 1 :

To verify,

( 33 + 45 ) + ( -26 )  =   33 + ( 45 + ( -26 )

LHS

3
+
 
4
+
 
-2 = 3x5 + 4x3 + -2
3 5 6 3x5 5x3 6

 

[ LCM of 3 and 5 is 15]

 

15
+
 
12 + -2
15 15 6

 

15+12
+
 
-2  = 27 -2 27 2
15  6 15 6 15 6

 

[LCM of 15 ans 6 is 90]

27x6
-
 
2x15 = 162 - 30 = 162- 30 = 132 = 2215
15x6 6x15 90 90 90 90

 

LHS = 2215

 

RHS   33 + ( 45 + ( -26 )  =   33 + ( 45 -26 )

3
+
 
4x6 - 2x5
3 5x6 6x5

 

[LCM of 5 and 6 is 30]

3
+
 
24 - 10 = 3

+

24-10 = 3 + 14
3 30 30 3 30 3 30

 

[LCM of 3 and 30 is 90]

 

3x30
+
 
14x3 = 90 + 42 = 90+(42) = 132 = 2215
3x30 30x3 90 90 90 90

 

RHS = 2215

LHS = RHS

Hence, associative property is true for addition.



9)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

24 , 26 and -25

RHS = Answer: 1330


SOLUTION 1 :

To verify,

( 24 + 26 ) + ( -25 )  =   24 + ( 26 + ( -25 )

LHS

2
+
 
2
+
 
-2 = 2x6 + 2x4 + -2
4 6 5 4x6 6x4 5

 

[ LCM of 4 and 6 is 24]

 

12
+
 
8 + -2
24 24 5

 

12+8
+
 
-2  = 20 -2 20 2
24  5 24 5 24 5

 

[LCM of 24 ans 5 is 120]

20x5
-
 
2x24 = 100 - 48 = 100- 48 = 52 = 1330
24x5 5x24 120 120 120 120

 

LHS = 1330

 

RHS   24 + ( 26 + ( -25 )  =   24 + ( 26 -25 )

2
+
 
2x5 - 2x6
4 6x5 5x6

 

[LCM of 6 and 5 is 30]

2
+
 
10 - 12 = 2

+

10-12 = 2 + -2
4 30 30 4 30 4 30

 

[LCM of 4 and 30 is 120]

 

2x30
+
 
-2x4 = 60 + -8 = 60+(-8) = 52 = 1330
4x30 30x4 120 120 120 120

 

RHS = 1330

LHS = RHS

Hence, associative property is true for addition.



10)  

 Verify whether associative property is satisfied for addition of the following pairs of rational numbers.(ples use /)

24 , 54 and -27

RHS = Answer: 4128


SOLUTION 1 :

To verify,

( 24 + 54 ) + ( -27 )  =   24 + ( 54 + ( -27 )

LHS

2
+
 
5
+
 
-2 = 2x4 + 5x4 + -2
4 4 7 4x4 4x4 7

 

[ LCM of 4 and 4 is 16]

 

8
+
 
20 + -2
16 16 7

 

8+20
+
 
-2  = 28 -2 28 2
16  7 16 7 16 7

 

[LCM of 16 ans 7 is 112]

28x7
-
 
2x16 = 196 - 32 = 196- 32 = 164 = 4128
16x7 7x16 112 112 112 112

 

LHS = 4128

 

RHS   24 + ( 54 + ( -27 )  =   24 + ( 54 -27 )

2
+
 
5x7 - 2x4
4 4x7 7x4

 

[LCM of 4 and 7 is 28]

2
+
 
35 - 8 = 2

+

35-8 = 2 + 27
4 28 28 4 28 4 28

 

[LCM of 4 and 28 is 112]

 

2x28
+
 
27x4 = 56 + 108 = 56+(108) = 164 = 4128
4x28 28x4 112 112 112 112

 

RHS = 4128

LHS = RHS

Hence, associative property is true for addition.