Scroll:Real Number System >> Rational Numbers ( Exercise 1.1) >> saq (4369)


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 subtraction of the following pairs of rational numbers.(ples use /)

23 , 56 and -47

LHS =

RHS =


Answer:_______________




2)  

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

24 , 45 and -55

LHS =

RHS =


Answer:_______________




3)  

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

23 , 36 and - 36

LHS =

RHS =


Answer:_______________




4)  

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

34 , 35 and -45

LHS =

RHS =


Answer:_______________




5)  

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

14 , 55 and -48

LHS =

RHS =


Answer:_______________




6)  

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

33 , 46 and -37

LHS =

RHS =


Answer:_______________




7)  

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

23 , 25 and -46

LHS =

RHS =


Answer:_______________




8)  

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

32 , 44 and -38

LHS =

RHS =


Answer:_______________




9)  

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

23 , 24 and -57

LHS =

RHS =


Answer:_______________




10)  

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

13 , 44 and -38

LHS =

RHS =


Answer:_______________




 

1)  

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

23 , 56 and -47

LHS = Answer: -2542

RHS = Answer: 1142


SOLUTION 1 :

To verify,

( 23 - ( 56 - ( -47 ))  =  ( 23 - 56 ) - ( -47 )

LHS

2
-
 
5
-
 
4 = 5x7 + 3x6
3 6 7 6x7 6x7

 

[ LCM of 6 and 7 is 42]

 

2
-
 
35
+
 
18
3 42 42

 

2
-
 
35+18
=
 
2  - 53 2x42 53x3
3 42  3 42 3x42 42x3

 

[LCM of 3 ans 42 is 126]

2x42
-
 
53x3 = 84 - 159 = 84- 159 = -75 = -2542
42x3 42x3 126 126 126 126

 

LHS = -2542

 

RHS  ( 23 - 56 ) - ( -47 )  =  ( 23 - ( 56 ) +47)

2x6
-
 
5x3 + 4
3x6 6x3 7

 

[LCM of 6 and 3 is 18] .....

12
-
 
-15 + 4 = 12-15

+

4 = -3 + 4
18 18 7 18 7 18 7

 

[LCM of 18 and 7 is 126]

 

-3x7
+
 
-3x3 = -21 + 54 = -21+(54) = 33 = 1142
18x7 18x3 126 126 126 126

 

RHS = 1142

LHS  RHS

Hence, associative property is not true for subtraction.



2)  

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

24 , 45 and -55

LHS = Answer: 11-10

RHS = Answer: 12


SOLUTION 1 :

To verify,

( 24 - ( 45 - ( -55 ))  =  ( 24 - 45 ) - ( -55 )

LHS

2
-
 
4
-
 
5 = 4x5 + 4x5
4 5 5 5x5 5x5

 

[ LCM of 5 and 5 is 25]

 

2
-
 
20
+
 
20
4 25 25

 

2
-
 
20+20
=
 
2  - 40 2x25 40x4
4 25  4 25 4x25 25x4

 

[LCM of 4 ans 25 is 100]

2x25
-
 
40x4 = 50 - 160 = 50- 160 = -110 = 11-10
25x4 25x4 100 100 100 100

 

LHS = 11-10

 

RHS  ( 24 - 45 ) - ( -55 )  =  ( 24 - ( 45 ) +55)

2x5
-
 
4x4 + 5
4x5 5x4 5

 

[LCM of 5 and 4 is 20] .....

10
-
 
-16 + 5 = 10-16

+

5 = -6 + 5
20 20 5 20 5 20 5

 

[LCM of 20 and 5 is 100]

 

-6x5
+
 
-6x4 = -30 + 80 = -30+(80) = 50 = 12
20x5 20x4 100 100 100 100

 

RHS = 12

LHS  RHS

Hence, associative property is not true for subtraction.



3)  

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

23 , 36 and - 36

LHS = Answer: 1-3

RHS = Answer: 23


SOLUTION 1 :

To verify,

( 23 - ( 36 - (- 36 ))  =  ( 23 - 36 ) - (- 36 )

LHS

2
-
 
3
-
 
3 = 3x6 + 3x6
3 6 6 6x6 6x6

 

[ LCM of 6 and 6 is 36]

 

2
-
 
18
+
 
18
3 36 36

 

2
-
 
18+18
=
 
2  - 36 2x36 36x3
3 36  3 36 3x36 36x3

 

[LCM of 3 ans 36 is 108]

2x36
-
 
36x3 = 72 - 108 = 72- 108 = -36 = 1-3
36x3 36x3 108 108 108 108

 

LHS = 1-3

 

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

2x6
-
 
3x3 + 3
3x6 6x3 6

 

[LCM of 6 and 3 is 18] .....

12
-
 
-9 + 3 = 12-9

+

3 = 3 + 3
18 18 6 18 6 18 6

 

[LCM of 18 and 6 is 108]

 

3x6
+
 
3x3 = 18 + 54 = 18+(54) = 72 = 23
18x6 18x3 108 108 108 108

 

RHS = 23

LHS  RHS

Hence, associative property is not true for subtraction.



4)  

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

34 , 35 and -45

LHS = Answer: -1320

RHS = Answer: 1920


SOLUTION 1 :

To verify,

( 34 - ( 35 - ( -45 ))  =  ( 34 - 35 ) - ( -45 )

LHS

3
-
 
3
-
 
4 = 3x5 + 4x5
4 5 5 5x5 5x5

 

[ LCM of 5 and 5 is 25]

 

3
-
 
15
+
 
20
4 25 25

 

3
-
 
15+20
=
 
3  - 35 3x25 35x4
4 25  4 25 4x25 25x4

 

[LCM of 4 ans 25 is 100]

3x25
-
 
35x4 = 75 - 140 = 75- 140 = -65 = -1320
25x4 25x4 100 100 100 100

 

LHS = -1320

 

RHS  ( 34 - 35 ) - ( -45 )  =  ( 34 - ( 35 ) +45)

3x5
-
 
3x4 + 4
4x5 5x4 5

 

[LCM of 5 and 4 is 20] .....

15
-
 
-12 + 4 = 15-12

+

4 = 3 + 4
20 20 5 20 5 20 5

 

[LCM of 20 and 5 is 100]

 

3x5
+
 
3x4 = 15 + 80 = 15+(80) = 95 = 1920
20x5 20x4 100 100 100 100

 

RHS = 1920

LHS  RHS

Hence, associative property is not true for subtraction.



5)  

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

14 , 55 and -48

LHS = Answer: 5-4

RHS = Answer: 1-4


SOLUTION 1 :

To verify,

( 14 - ( 55 - ( -48 ))  =  ( 14 - 55 ) - ( -48 )

LHS

1
-
 
5
-
 
4 = 5x8 + 4x5
4 5 8 5x8 5x8

 

[ LCM of 5 and 8 is 40]

 

1
-
 
40
+
 
20
4 40 40

 

1
-
 
40+20
=
 
1  - 60 1x40 60x4
4 40  4 40 4x40 40x4

 

[LCM of 4 ans 40 is 160]

1x40
-
 
60x4 = 40 - 240 = 40- 240 = -200 = 5-4
40x4 40x4 160 160 160 160

 

LHS = 5-4

 

RHS  ( 14 - 55 ) - ( -48 )  =  ( 14 - ( 55 ) +48)

1x5
-
 
5x4 + 4
4x5 5x4 8

 

[LCM of 5 and 4 is 20] .....

5
-
 
-20 + 4 = 5-20

+

4 = -15 + 4
20 20 8 20 8 20 8

 

[LCM of 20 and 8 is 160]

 

-15x8
+
 
-15x4 = -120 + 80 = -120+(80) = -40 = 1-4
20x8 20x4 160 160 160 160

 

RHS = 1-4

LHS  RHS

Hence, associative property is not true for subtraction.



6)  

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

33 , 46 and -37

LHS = Answer: -221

RHS = Answer: 1621


SOLUTION 1 :

To verify,

( 33 - ( 46 - ( -37 ))  =  ( 33 - 46 ) - ( -37 )

LHS

3
-
 
4
-
 
3 = 4x7 + 3x6
3 6 7 6x7 6x7

 

[ LCM of 6 and 7 is 42]

 

3
-
 
28
+
 
18
3 42 42

 

3
-
 
28+18
=
 
3  - 46 3x42 46x3
3 42  3 42 3x42 42x3

 

[LCM of 3 ans 42 is 126]

3x42
-
 
46x3 = 126 - 138 = 126- 138 = -12 = -221
42x3 42x3 126 126 126 126

 

LHS = -221

 

RHS  ( 33 - 46 ) - ( -37 )  =  ( 33 - ( 46 ) +37)

3x6
-
 
4x3 + 3
3x6 6x3 7

 

[LCM of 6 and 3 is 18] .....

18
-
 
-12 + 3 = 18-12

+

3 = 6 + 3
18 18 7 18 7 18 7

 

[LCM of 18 and 7 is 126]

 

6x7
+
 
6x3 = 42 + 54 = 42+(54) = 96 = 1621
18x7 18x3 126 126 126 126

 

RHS = 1621

LHS  RHS

Hence, associative property is not true for subtraction.



7)  

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

23 , 25 and -46

LHS = Answer: 7-30

RHS = Answer: 2330


SOLUTION 1 :

To verify,

( 23 - ( 25 - ( -46 ))  =  ( 23 - 25 ) - ( -46 )

LHS

2
-
 
2
-
 
4 = 2x6 + 3x5
3 5 6 5x6 5x6

 

[ LCM of 5 and 6 is 30]

 

2
-
 
12
+
 
15
3 30 30

 

2
-
 
12+15
=
 
2  - 27 2x30 27x3
3 30  3 30 3x30 30x3

 

[LCM of 3 ans 30 is 90]

2x30
-
 
27x3 = 60 - 81 = 60- 81 = -21 = 7-30
30x3 30x3 90 90 90 90

 

LHS = 7-30

 

RHS  ( 23 - 25 ) - ( -46 )  =  ( 23 - ( 25 ) +46)

2x5
-
 
2x3 + 4
3x5 5x3 6

 

[LCM of 5 and 3 is 15] .....

10
-
 
-6 + 4 = 10-6

+

4 = 4 + 4
15 15 6 15 6 15 6

 

[LCM of 15 and 6 is 90]

 

4x6
+
 
4x3 = 24 + 45 = 24+(45) = 69 = 2330
15x6 15x3 90 90 90 90

 

RHS = 2330

LHS  RHS

Hence, associative property is not true for subtraction.



8)  

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

32 , 44 and -38

LHS = Answer: 14

RHS = Answer: 34


SOLUTION 1 :

To verify,

( 32 - ( 44 - ( -38 ))  =  ( 32 - 44 ) - ( -38 )

LHS

3
-
 
4
-
 
3 = 4x8 + 2x4
2 4 8 4x8 4x8

 

[ LCM of 4 and 8 is 32]

 

3
-
 
32
+
 
8
2 32 32

 

3
-
 
32+8
=
 
3  - 40 3x32 40x2
2 32  2 32 2x32 32x2

 

[LCM of 2 ans 32 is 64]

3x32
-
 
40x2 = 96 - 80 = 96- 80 = 16 = 14
32x2 32x2 64 64 64 64

 

LHS = 14

 

RHS  ( 32 - 44 ) - ( -38 )  =  ( 32 - ( 44 ) +38)

3x4
-
 
4x2 + 3
2x4 4x2 8

 

[LCM of 4 and 2 is 8] .....

12
-
 
-8 + 3 = 12-8

+

3 = 4 + 3
8 8 8 8 8 8 8

 

[LCM of 8 and 8 is 64]

 

4x8
+
 
4x2 = 32 + 16 = 32+(16) = 48 = 34
8x8 8x2 64 64 64 64

 

RHS = 34

LHS  RHS

Hence, associative property is not true for subtraction.



9)  

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

23 , 24 and -57

LHS = Answer: -1142

RHS = Answer: 2542


SOLUTION 1 :

To verify,

( 23 - ( 24 - ( -57 ))  =  ( 23 - 24 ) - ( -57 )

LHS

2
-
 
2
-
 
5 = 2x7 + 3x4
3 4 7 4x7 4x7

 

[ LCM of 4 and 7 is 28]

 

2
-
 
14
+
 
12
3 28 28

 

2
-
 
14+12
=
 
2  - 26 2x28 26x3
3 28  3 28 3x28 28x3

 

[LCM of 3 ans 28 is 84]

2x28
-
 
26x3 = 56 - 78 = 56- 78 = -22 = -1142
28x3 28x3 84 84 84 84

 

LHS = -1142

 

RHS  ( 23 - 24 ) - ( -57 )  =  ( 23 - ( 24 ) +57)

2x4
-
 
2x3 + 5
3x4 4x3 7

 

[LCM of 4 and 3 is 12] .....

8
-
 
-6 + 5 = 8-6

+

5 = 2 + 5
12 12 7 12 7 12 7

 

[LCM of 12 and 7 is 84]

 

2x7
+
 
2x3 = 14 + 36 = 14+(36) = 50 = 2542
12x7 12x3 84 84 84 84

 

RHS = 2542

LHS  RHS

Hence, associative property is not true for subtraction.



10)  

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

13 , 44 and -38

LHS = Answer: 25-24

RHS = Answer: 7-24


SOLUTION 1 :

To verify,

( 13 - ( 44 - ( -38 ))  =  ( 13 - 44 ) - ( -38 )

LHS

1
-
 
4
-
 
3 = 4x8 + 3x4
3 4 8 4x8 4x8

 

[ LCM of 4 and 8 is 32]

 

1
-
 
32
+
 
12
3 32 32

 

1
-
 
32+12
=
 
1  - 44 1x32 44x3
3 32  3 32 3x32 32x3

 

[LCM of 3 ans 32 is 96]

1x32
-
 
44x3 = 32 - 132 = 32- 132 = -100 = 25-24
32x3 32x3 96 96 96 96

 

LHS = 25-24

 

RHS  ( 13 - 44 ) - ( -38 )  =  ( 13 - ( 44 ) +38)

1x4
-
 
4x3 + 3
3x4 4x3 8

 

[LCM of 4 and 3 is 12] .....

4
-
 
-12 + 3 = 4-12

+

3 = -8 + 3
12 12 8 12 8 12 8

 

[LCM of 12 and 8 is 96]

 

-8x8
+
 
-8x3 = -64 + 36 = -64+(36) = -28 = 7-24
12x8 12x3 96 96 96 96

 

RHS = 7-24

LHS  RHS

Hence, associative property is not true for subtraction.