S Chand ICSE Mathematics Class 6 Solution Third Chapter Negative Numbers and Integers Exercise 3B (O.P. Malhotra, S.K. Gupta, Anubhuti Gangal)
EXERCISE 3B
(1) Write the addition sentences shown by the following number lines.
(i) – 3 + 5 = 2
(ii) 9 + (- 2) = 7
(iii) (- 2) + (- 4) = – 6
(iv) – 5 + 13 = 8
(v) – 4 + 4 = 0
(2) Use the number line and add the following integers.
(3) Add without using the number line.
(i) – 8 + (- 4) = – 12
(ii) 5 + (- 4) = 1
(iii) – 17 + 24 = 7
(iv) 0 + (- 36) = – 36
(v) 27 + (- 27) = 0
(vi) – 692 + 258 = – 434
(vii) 4004 + (- 999) = 3005
(viii) – 1530 + 0 = – 1530
(ix) 5987 + (- 5987) = 0
(x) 3958 + (- 3959) = – 1
(xi) – 712 + 2538 + 712
= – 712 + 712 + 2538
= 2538
(xii) – 729 + (- 7098) + 729
= – 729 + 729 – 7098
= 7098
(4) – 7 + 10 = 3 km
Ans: 3 km high above the sea level is the tip of the iceberg.
(5) – 10 + 5 – 4 – 3 + 15
= – 10 – 4 – 3 + 5 + 15
= – 17 + 20
= 3
The final score is +3.
(6) Find the sum.
(i) 200 + (- 55) + (- 77) + (- 68)
= 200 – 55 – 77 – 68
= 200 – 200
= 0
(ii) 1393 + (- 407) + (- 872) + 690
= 1393 + 690 – 407 – 872
= 2083 – 1279
= 804
(iii) 703 + (- 3) + (- 1) + 1 + (- 400) + 0
= 703 + 1 – 3 – 1 – 400
= 704 – 404
= 300
(iv) 2000 + 516 + (- 517) – 1999
= 2516 – 2516
= 0
(7) Write the addition sentence corresponding to each of the following subtraction sentences.
(i) 1 + (- 8)
(ii) – 8 + (- 11)
(iii) 4 + 3
(iv) – 9 + 12
(v) – 10 + 7
(8) Find:
(i) 5 – 9 = – 4
(ii) 2 – (- 7)
= 2 + 7 = 9
(iii) – 11 – (- 9)
= – 11 + 9 = – 2
(iv) – 9 – (- 12)
= – 9 + 12 = 3
(v) 0 – 75 = – 75
(vi) 0 – (- 45) = 45
(9) Write the successor and predecessor of each of the following.
(i) 6, 4
(ii) – 2, – 4
(iii) – 99, – 101
(iv) 1, – 1
(10) Subtract the first integer from the second in each of the following.
(i) – 2 – 8 = – 10
(ii) – 12 – (- 15)
= – 12 + 15 = 3
(iii) 307 – (- 93)
= 307 + 93
= 400
(iv) 0 – (- 267)= 267
(v) 7003 – 0 = 7003
(vi) – 45632 – (- 35632)
= – 45632 + 35632
= – 10000
(11) Find the value of:
(i) – 8 – (- 15) – 10
= – 8 – 10 + 15
= – 18 + 15 = – 3
(ii) 6 – 7 – (- 23)
= 6 + 23 – 7
= 29 – 7 = 22
(iii) (3 – 4) + (3 – 4)
= – 1 – 1 = – 2
(iv) – 60 – (- 58) – (- 2)
= – 60 + 58 + 2
= – 60 + 60 = 0
(12) Fill in the blanks by <, > or = to make each sentence true.
(i) (- 3) + (- 7) < (- 3) – (- 7)
= (- 3 – 7) < (- 3 + 7)
= – 10 < + 4
(ii) (- 23) – (- 23) > (- 23) + (- 23)
= (- 23 + 23) > (- 23 – 23)
= 0 > – 46
(iii) – (30) – 30 < – 30 + 30
= (- 30 – 30) < (- 30 + 30)
= – 60 < 0
(iv) (- 15) + (- 25) = (- 25) – 15
= (- 15 – 25) = (-25 – 15)
= – 45 = – 45
(13) The difference between the inside and outside temperature is
= – 10o – (- 35)o
= – 10o + 35o
= 25o C
(14) The maximum temperature than the minimum temperature is
= 130o – (- 110o)
= 130o + 110o = 140o C
(15) Subtract the sum of
(i) – 45 – (- 340 + 170)
= – 45 + 340 – 170
= – 215 + 340 = 125
(ii) (- 385 – 675) – {865 + (- 493)}
= – 1060 – 865 + 493
= – 1925 + 493 = – 1432
Multiple choice Questions (MCQs)
(16) (b) – 250 + (- 75)
(17) (c) – 10 + 8
(18) (c) The sum of two negative integers is a negative integer.
(19) (c) – 53 + 72
(20) (b) 4 – (- 1)
(21) (a) 2754
(22) 45 – 23 = (b) 22
(23) Answer True (T) or False (F).
(i) T
(ii) F
(iii) F
(iv) F
(24) (d) – 1.
Thanks for this ………..