Page 29 - Revised Maths Wisdom Class - 6

The Other Side of Zero 27

Solution: (a) (–6) + 13 + (–3) + 18 (b) 68 + (–2) + (–7) + (–80)
= 7 + 15 = 22 = 68 + (–89) = –21

Example 5: Find an integer x such that:
(a) x + 5 = 0 (b) x + (–9) = 0

Solution: (a) x + 5 = 0 (b) x + (–9) = 0
Adding (–5) on both sides, Adding 9 on both sides,

⇒ x + 5 + (–5) = 0 + (–5) ⇒ x + 9 + (–9) = 0 + 9
⇒ x = –5 ⇒ x = 9

Exercise 2B
Exercise 2B
1. Using the number line write the integer which is:
(a) 6 more than 4 (b) 3 more than – 4 (c) –5 more than –3
2. Add the following without using the number line.
(a) –16 + 24 (b) (–18) + (–16) (c) 66 + (–21)
(d) (–535) + (–609) (e) –1000 + 186 (f) 86 + (–193) + 65

3. Find the sum of the following:
(a) –2341 and 10000 (b) –638, 943 and –111
(c) 441, 291 and –12546 (d) –87, –199 and –1347

4. Evaluate:
(a) (–36) + 11 + (–73) (b) 84 + (–99) + (–135)

(c) (–83) + (–183) + (1833) (d) 900 + (–90) + (–1000)

5. Fill by >, < or =

(a) (–7) + (–3) (–9) + (4) (b) (–15) + (14) (–17) + (–11)

(c) (–27) + (–22) (–24) – (–25) (d) (90) + (–40) (–40) + (70)

(e) (–7) + (–13) (–13) – (–6)
6. What should be added to –1984 to get the integer –1?

7. Rohan withdraw ` 8000 from his bank and deposited ` 2000 the next day. If the initial balance was
` 12000, how much more money he should deposit to make the balance ` 12000 again?

8. Find the additive inverse of each of the following:
(a) 69 (b) 0 (c) –138 (d) 1

9. Write the successor and predecessor of each of the following:
(a) 0 (b) –9 (c) 1001 (d) –189

10. Find an integer p such that:
(a) p + 11 = 0 (b) p + (–3) = 0
11. A submarine was situated 800 m below sea level. If it ascends 235 m, what is its new position?