Page 31 - Maths Skill - 6

The Other Side of Zero 29

Let’s Attempt

Example 1: Subtract the following:
(i) – 7 from 4 (ii) 5 from – 4 (iii) – 3 from – 4 (iv) 8 from 3
Solution: (i) 4 – (– 7) = 4 + 7 = 11 (ii) – 4 – (5) = – 4 + (– 5) = – 9

(iii) – 4 – (– 3) = – 4 + 3 = – 1 (iv) 3 – (8) = 3 + (– 8) = – 5

Example 2: Find:
(i) 40 – (25) (ii) 62 – (– 80) (iii) – 22 – (50) (iv) 13 – (– 22)

Solution: (i) 40 + (– 25) = 15 (ii) 62 + (+ 80) = 142
(iii) – 22 + (– 50) = – 72 (iv) 13 + (+ 22) = 35

Example 3: Fill in the blank with > or <.

(i) (– 5) + (– 4) (– 5) – (– 4) (ii) (– 16) – (– 23) (– 27) + (– 33)

(iii) 73 – (– 17) 65 + (– 22) (iv) (– 33) – (– 68) (– 68) – (– 33)
Solution: (i) L.H.S. = (– 5) + (– 4) = – 9 (iii) L.H.S. = 73 – (– 17) = 73 + 17 = 90

R.H.S. = (– 5) – (– 4) = (– 5) + (4) = – 1 R.H.S. = 65 + (– 22) = 43
Now, – 1 > – 9 Now, 90 > 43

Therefore, (– 5) + (– 4) < (– 5) – (– 4) Therefore, L.H.S. > R.H.S.
(ii) L.H.S. = – 16 – (– 23) = – 16 + (+ 23) = 7 Or, 73 – (– 17) > (65) + (–22)
R.H.S. = (– 27) + (– 33) = – 60 (iv) L.H.S. = (– 33) – (– 68) = – 33 + 68 = 35

Now, 7 > – 60 R.H.S. = (– 68) – (– 33) = – 68 + 33 = – 35
Therefore, L.H.S. > R.H.S. Now, 35 > – 35, So L.H.S. > R.H.S.

Or, (– 16) – (– 23) > (– 27) + (– 33) Or, (– 33) – (– 68) > (– 68) – (– 33)

Exercise 2.3

1. Subtract.
(i) 36 from – 292 (ii) – 68 from – 55 (iii) 0 from – 453

(iv) – 453 from 0 (v) – 450 from 450 (vi) – 318 from – 318
2. Fill in the blanks.

(i) – 9 + _____ = 0 (ii) 13 + (– 11) = _____ (iii) 232 + _____ = – 30
(iv) _____ + 215 = – 35 (v) – 109 + _____ = – 210 (vi) – 15 + (– 16) = _____
3. Insert the appropriate symbol ‘<’ or ‘>’ or ‘=’ in the following blanks.

(i) ( – 5) + (5) _____ 9 + (– 9) (ii) 30 – (– 62) _____ 62 + 30
(iii) 13 + (– 8) _____ 13 + 8 (iv) 15 + (– 9) _____ (– 15) – (– 9)
(v) – 65 + (– 40) _____ (– 100) + (– 25) (vi) (– 32 + 392) _____ (– 32) – 392