RS Aggarwal Class 6 Math Fourth Chapter Integers Exercise 4D Solution

RS Aggarwal Class 6 Math Fourth Chapter Integers Exercise 4D Solution

EXERCISE 4D

(1) Multiply:

(i) 15 by 9

= 15 x 9

= 135

(ii) 18 by -7

= 18 x (-7)

= – 126

(iii) 29 by -11

= 29 x (-11)

= – 319

(iv) -18 by 13

= (-18) x 13

= – 234

(v) – 56 by 16

= (- 56) x 16

= – 896

(vi) 32 by – 21

= 32 x (- 21)

= – 672

(vii) – 57 by 0

= – 57 x 0

= 0

(viii) 0 by – 31

= 0 x (- 31)

= 0

(ix) – 12 by – 9

= (-12) x (- 9)

= 108

(x) – 746 by – 8

= ( – 746) x (- 8)

= 5968

(xi) 118 by – 7

= 118 x (- 7)

= – 826

(xii) – 238 by -143

= (- 238) x ( -143)

= 34034

(2) Find the products:

(i) (-2) x 3 x (- 4)

= – 6 x (- 4)

= 24

(ii) 2 x (- 5) x (- 6)

= 2 x 30

= 60

(iii) ( -8) x 3 x 5

= (- 8) x 15

= – 120

(iv) 8 x 7 x (- 10)

= 56 x (- 10)

= – 560

(v) (-3) x (-7) x (-6)

= (-3) x 42

= – 246

(vi) (-8) x (-3) x (-9)

= (-8) x 27

= – 216

(3) Use convenient groupings and find the values of

(i) 18 x (- 27) x 30

= 18 x (- 810)

= – 14580

(ii) (- 8) x (-63) x 9

= ( -8) x (- 567)

= 4536

(iii) ( -17) x (- 23) x 41

= (-17) x (- 943)

= 16031

(iv) (- 51) x (- 47) x (- 19)

= (- 51) x 893

= – 45543

(4) Verify the following:

(i) 18 x [9 + (- 7)]= 18 x 9 + 18 x (-7)

L. H. S

18 x [9 + (- 7)]

= 18 x 2

= 36

R. H. S

18 x 9 + 18 x (-7)

= 162 + (- 126)

= 36

So, L. H. S= R. H. S (Proved)

(ii) (- 13) x [(- 6) + (- 19)] = (- 13) x (- 6) + (- 13) x (- 19)

L. H. S

(- 13) x [(- 6) + (- 19)]

= (- 13) x [ – 6 – 19]

= (- 13) x (- 25)

= 325

R. H. S

(- 13) x (- 6) + (- 13) x (- 19)

= 78 + 247

= 325

L. H. S = R. H. S (Proved)

(5) Complete the following multiplication table:

x	-3	-2	-1	0	1	2	3
-3	+9	+6	+3	0	-3	-6	-9
-2	+6	+4	+2	0	-2	-4	-6
-1	+3	+2	+1	0	-1	-2	-3
0	0	0	0	0	0	0	0
1	-3	-2	-1	0	1	2	3
2	-6	-4	-2	0	2	4	6
3	-9	-6	-3	0	3	6	9

(6) Which of the following statements are true and which are false?

(i) The product of a positive integer and a negative integer is negative.

Ans: True

(ii) The product of two negative integers is a negative integer.

Ans: False

(iii) The product of three negative integers is a negative integer.

Ans: True

(iv) Every integer when multiplied with – 1 gives its multiplicative inverse.

Ans: False

(7) Simplify:

(i) (-9) x 6 + (-9) x 4

= (- 54) + (- 36)

= – 54 – 36

= – 90

(ii) 8 x (- 12) + 7 x (-12)

= (- 96) + ( – 84)

= – 96 – 84

= – 180

(iii) 30 x (-22) + 30 x (14)

= (- 660) + 420

= – 240

(iv) (- 15) x (- 14) + (- 15) x (- 6)

= 210 + 90

= 300

(v) 43 x (- 33) + 43 x (- 17)

= (- 1419) + (- 731)

= – 1419 – 731

= – 2150

(vi) (-36) x (72) + (- 36) x 28

= (- 2592) + (- 1008)

= – 2592 – 1008

= – 3600

(vii) (- 27) x (- 16) + (- 27) x  (- 14)

= 432 + 378

= 810