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 /)

14 , 55 and -27

RHS =


Answer:_______________




2)  

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

23 , 35 and -45

RHS =


Answer:_______________




3)  

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

34 , 54 and -36

RHS =


Answer:_______________




4)  

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

22 , 34 and -26

RHS =


Answer:_______________




5)  

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

34 , 45 and -46

RHS =


Answer:_______________




6)  

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

13 , 34 and -37

RHS =


Answer:_______________




7)  

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

34 , 26 and -27

RHS =


Answer:_______________




8)  

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

14 , 45 and -38

RHS =


Answer:_______________




9)  

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

34 , 46 and -38

RHS =


Answer:_______________




10)  

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

24 , 35 and -48

RHS =


Answer:_______________




 

1)  

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

14 , 55 and -27

RHS = Answer: 2728


SOLUTION 1 :

To verify,

( 14 + 55 ) + ( -27 )  =   14 + ( 55 + ( -27 )

LHS

1
+
 
5
+
 
-2 = 1x5 + 5x4 + -2
4 5 7 4x5 5x4 7

 

[ LCM of 4 and 5 is 20]

 

5
+
 
20 + -2
20 20 7

 

5+20
+
 
-2  = 25 -2 25 2
20  7 20 7 20 7

 

[LCM of 20 ans 7 is 140]

25x7
-
 
2x20 = 175 - 40 = 175- 40 = 135 = 2728
20x7 7x20 140 140 140 140

 

LHS = 2728

 

RHS   14 + ( 55 + ( -27 )  =   14 + ( 55 -27 )

1
+
 
5x7 - 2x5
4 5x7 7x5

 

[LCM of 5 and 7 is 35]

1
+
 
35 - 10 = 1

+

35-10 = 1 + 25
4 35 35 4 35 4 35

 

[LCM of 4 and 35 is 140]

 

1x35
+
 
25x4 = 35 + 100 = 35+(100) = 135 = 2728
4x35 35x4 140 140 140 140

 

RHS = 2728

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 /)

23 , 35 and -45

RHS = Answer: 715


SOLUTION 1 :

To verify,

( 23 + 35 ) + ( -45 )  =   23 + ( 35 + ( -45 )

LHS

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

 

[ LCM of 3 and 5 is 15]

 

10
+
 
9 + -4
15 15 5

 

10+9
+
 
-4  = 19 -4 19 4
15  5 15 5 15 5

 

[LCM of 15 ans 5 is 75]

19x5
-
 
4x15 = 95 - 60 = 95- 60 = 35 = 715
15x5 5x15 75 75 75 75

 

LHS = 715

 

RHS   23 + ( 35 + ( -45 )  =   23 + ( 35 -45 )

2
+
 
3x5 - 4x5
3 5x5 5x5

 

[LCM of 5 and 5 is 25]

2
+
 
15 - 20 = 2

+

15-20 = 2 + -5
3 25 25 3 25 3 25

 

[LCM of 3 and 25 is 75]

 

2x25
+
 
-5x3 = 50 + -15 = 50+(-15) = 35 = 715
3x25 25x3 75 75 75 75

 

RHS = 715

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 , 54 and -36

RHS = Answer: 32


SOLUTION 1 :

To verify,

( 34 + 54 ) + ( -36 )  =   34 + ( 54 + ( -36 )

LHS

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

 

[ LCM of 4 and 4 is 16]

 

12
+
 
20 + -3
16 16 6

 

12+20
+
 
-3  = 32 -3 32 3
16  6 16 6 16 6

 

[LCM of 16 ans 6 is 96]

32x6
-
 
3x16 = 192 - 48 = 192- 48 = 144 = 32
16x6 6x16 96 96 96 96

 

LHS = 32

 

RHS   34 + ( 54 + ( -36 )  =   34 + ( 54 -36 )

3
+
 
5x6 - 3x4
4 4x6 6x4

 

[LCM of 4 and 6 is 24]

3
+
 
30 - 12 = 3

+

30-12 = 3 + 18
4 24 24 4 24 4 24

 

[LCM of 4 and 24 is 96]

 

3x24
+
 
18x4 = 72 + 72 = 72+(72) = 144 = 32
4x24 24x4 96 96 96 96

 

RHS = 32

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 /)

22 , 34 and -26

RHS = Answer: 1712


SOLUTION 1 :

To verify,

( 22 + 34 ) + ( -26 )  =   22 + ( 34 + ( -26 )

LHS

2
+
 
3
+
 
-2 = 2x4 + 3x2 + -2
2 4 6 2x4 4x2 6

 

[ LCM of 2 and 4 is 8]

 

8
+
 
6 + -2
8 8 6

 

8+6
+
 
-2  = 14 -2 14 2
6 8 6 8 6

 

[LCM of 8 ans 6 is 48]

14x6
-
 
2x8 = 84 - 16 = 84- 16 = 68 = 1712
8x6 6x8 48 48 48 48

 

LHS = 1712

 

RHS   22 + ( 34 + ( -26 )  =   22 + ( 34 -26 )

2
+
 
3x6 - 2x4
2 4x6 6x4

 

[LCM of 4 and 6 is 24]

2
+
 
18 - 8 = 2

+

18-8 = 2 + 10
2 24 24 2 24 2 24

 

[LCM of 2 and 24 is 48]

 

2x24
+
 
10x2 = 48 + 20 = 48+(20) = 68 = 1712
2x24 24x2 48 48 48 48

 

RHS = 1712

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 , 45 and -46

RHS = Answer: 5360


SOLUTION 1 :

To verify,

( 34 + 45 ) + ( -46 )  =   34 + ( 45 + ( -46 )

LHS

3
+
 
4
+
 
-4 = 3x5 + 4x4 + -4
4 5 6 4x5 5x4 6

 

[ LCM of 4 and 5 is 20]

 

15
+
 
16 + -4
20 20 6

 

15+16
+
 
-4  = 31 -4 31 4
20  6 20 6 20 6

 

[LCM of 20 ans 6 is 120]

31x6
-
 
4x20 = 186 - 80 = 186- 80 = 106 = 5360
20x6 6x20 120 120 120 120

 

LHS = 5360

 

RHS   34 + ( 45 + ( -46 )  =   34 + ( 45 -46 )

3
+
 
4x6 - 4x5
4 5x6 6x5

 

[LCM of 5 and 6 is 30]

3
+
 
24 - 20 = 3

+

24-20 = 3 + 4
4 30 30 4 30 4 30

 

[LCM of 4 and 30 is 120]

 

3x30
+
 
4x4 = 90 + 16 = 90+(16) = 106 = 5360
4x30 30x4 120 120 120 120

 

RHS = 5360

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 /)

13 , 34 and -37

RHS = Answer: 5584


SOLUTION 1 :

To verify,

( 13 + 34 ) + ( -37 )  =   13 + ( 34 + ( -37 )

LHS

1
+
 
3
+
 
-3 = 1x4 + 3x3 + -3
3 4 7 3x4 4x3 7

 

[ LCM of 3 and 4 is 12]

 

4
+
 
9 + -3
12 12 7

 

4+9
+
 
-3  = 13 -3 13 3
12  7 12 7 12 7

 

[LCM of 12 ans 7 is 84]

13x7
-
 
3x12 = 91 - 36 = 91- 36 = 55 = 5584
12x7 7x12 84 84 84 84

 

LHS = 5584

 

RHS   13 + ( 34 + ( -37 )  =   13 + ( 34 -37 )

1
+
 
3x7 - 3x4
3 4x7 7x4

 

[LCM of 4 and 7 is 28]

1
+
 
21 - 12 = 1

+

21-12 = 1 + 9
3 28 28 3 28 3 28

 

[LCM of 3 and 28 is 84]

 

1x28
+
 
9x3 = 28 + 27 = 28+(27) = 55 = 5584
3x28 28x3 84 84 84 84

 

RHS = 5584

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 /)

34 , 26 and -27

RHS = Answer: 6784


SOLUTION 1 :

To verify,

( 34 + 26 ) + ( -27 )  =   34 + ( 26 + ( -27 )

LHS

3
+
 
2
+
 
-2 = 3x6 + 2x4 + -2
4 6 7 4x6 6x4 7

 

[ LCM of 4 and 6 is 24]

 

18
+
 
8 + -2
24 24 7

 

18+8
+
 
-2  = 26 -2 26 2
24  7 24 7 24 7

 

[LCM of 24 ans 7 is 168]

26x7
-
 
2x24 = 182 - 48 = 182- 48 = 134 = 6784
24x7 7x24 168 168 168 168

 

LHS = 6784

 

RHS   34 + ( 26 + ( -27 )  =   34 + ( 26 -27 )

3
+
 
2x7 - 2x6
4 6x7 7x6

 

[LCM of 6 and 7 is 42]

3
+
 
14 - 12 = 3

+

14-12 = 3 + 2
4 42 42 4 42 4 42

 

[LCM of 4 and 42 is 168]

 

3x42
+
 
2x4 = 126 + 8 = 126+(8) = 134 = 6784
4x42 42x4 168 168 168 168

 

RHS = 6784

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 /)

14 , 45 and -38

RHS = Answer: 2740


SOLUTION 1 :

To verify,

( 14 + 45 ) + ( -38 )  =   14 + ( 45 + ( -38 )

LHS

1
+
 
4
+
 
-3 = 1x5 + 4x4 + -3
4 5 8 4x5 5x4 8

 

[ LCM of 4 and 5 is 20]

 

5
+
 
16 + -3
20 20 8

 

5+16
+
 
-3  = 21 -3 21 3
20  8 20 8 20 8

 

[LCM of 20 ans 8 is 160]

21x8
-
 
3x20 = 168 - 60 = 168- 60 = 108 = 2740
20x8 8x20 160 160 160 160

 

LHS = 2740

 

RHS   14 + ( 45 + ( -38 )  =   14 + ( 45 -38 )

1
+
 
4x8 - 3x5
4 5x8 8x5

 

[LCM of 5 and 8 is 40]

1
+
 
32 - 15 = 1

+

32-15 = 1 + 17
4 40 40 4 40 4 40

 

[LCM of 4 and 40 is 160]

 

1x40
+
 
17x4 = 40 + 68 = 40+(68) = 108 = 2740
4x40 40x4 160 160 160 160

 

RHS = 2740

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 /)

34 , 46 and -38

RHS = Answer: 2524


SOLUTION 1 :

To verify,

( 34 + 46 ) + ( -38 )  =   34 + ( 46 + ( -38 )

LHS

3
+
 
4
+
 
-3 = 3x6 + 4x4 + -3
4 6 8 4x6 6x4 8

 

[ LCM of 4 and 6 is 24]

 

18
+
 
16 + -3
24 24 8

 

18+16
+
 
-3  = 34 -3 34 3
24  8 24 8 24 8

 

[LCM of 24 ans 8 is 192]

34x8
-
 
3x24 = 272 - 72 = 272- 72 = 200 = 2524
24x8 8x24 192 192 192 192

 

LHS = 2524

 

RHS   34 + ( 46 + ( -38 )  =   34 + ( 46 -38 )

3
+
 
4x8 - 3x6
4 6x8 8x6

 

[LCM of 6 and 8 is 48]

3
+
 
32 - 18 = 3

+

32-18 = 3 + 14
4 48 48 4 48 4 48

 

[LCM of 4 and 48 is 192]

 

3x48
+
 
14x4 = 144 + 56 = 144+(56) = 200 = 2524
4x48 48x4 192 192 192 192

 

RHS = 2524

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 , 35 and -48

RHS = Answer: 35


SOLUTION 1 :

To verify,

( 24 + 35 ) + ( -48 )  =   24 + ( 35 + ( -48 )

LHS

2
+
 
3
+
 
-4 = 2x5 + 3x4 + -4
4 5 8 4x5 5x4 8

 

[ LCM of 4 and 5 is 20]

 

10
+
 
12 + -4
20 20 8

 

10+12
+
 
-4  = 22 -4 22 4
20  8 20 8 20 8

 

[LCM of 20 ans 8 is 160]

22x8
-
 
4x20 = 176 - 80 = 176- 80 = 96 = 35
20x8 8x20 160 160 160 160

 

LHS = 35

 

RHS   24 + ( 35 + ( -48 )  =   24 + ( 35 -48 )

2
+
 
3x8 - 4x5
4 5x8 8x5

 

[LCM of 5 and 8 is 40]

2
+
 
24 - 20 = 2

+

24-20 = 2 + 4
4 40 40 4 40 4 40

 

[LCM of 4 and 40 is 160]

 

2x40
+
 
4x4 = 80 + 16 = 80+(16) = 96 = 35
4x40 40x4 160 160 160 160

 

RHS = 35

LHS = RHS

Hence, associative property is true for addition.