Class 6 Maths Chapter 10: The Other Side of Zero (Solved)
Note: Refer to your textbook for diagrams and images. See image/page numbers mentioned.
Page 245: Addition to keep track of movement
1. Start from Floor +2 and press –3. Where will you reach?
Expression: (+2) + (–3) = –1
You will reach Floor –1.
You will reach Floor –1.
2. Evaluate the expressions:
a. (+1) + (+4) = +5
b. (+4) + (+1) = +5
c. (+4) + (–3) = +1
d. (–1) + (+2) = +1
e. (–1) + (+1) = 0
f. 0 + (+2) = +2
g. 0 + (–2) = –2
b. (+4) + (+1) = +5
c. (+4) + (–3) = +1
d. (–1) + (+2) = +1
e. (–1) + (+1) = 0
f. 0 + (+2) = +2
g. 0 + (–2) = –2
3. Movements to reach Floor –5:
• (+3) + (–8) = –5
• (+1) + (–6) = –5
• (0) + (–5) = –5
• (–2) + (–3) = –5
• (+1) + (–6) = –5
• (0) + (–5) = –5
• (–2) + (–3) = –5
Page 246: Combining button presses
Evaluate:
a. (+1) + (+4) = +5
b. (+4) + (+1) = +5
c. (+4) + (–3) + (–2) = –1
d. (–1) + (+2) + (–3) = –2
b. (+4) + (+1) = +5
c. (+4) + (–3) + (–2) = –1
d. (–1) + (+2) + (–3) = –2
Page 247–249: Subtraction and inverses
Write inverses:
• +4 → –4
• –4 → +4
• –3 → +3
• 0 → 0
• +2 → –2
• –1 → +1
• –4 → +4
• –3 → +3
• 0 → 0
• +2 → –2
• –1 → +1
Compare using < or >:
a. –2 < +5
b. –5 < +4
c. –5 > –3
d. +6 > –6
e. 0 > –4
f. 0 < +4
b. –5 < +4
c. –5 > –3
d. +6 > –6
e. 0 > –4
f. 0 < +4
More comparisons:
a. –10 > –12
b. +17 > –10
c. 0 > –20
d. +9 > –9
e. –25 < –7
f. +15 > –17
b. +17 > –10
c. 0 > –20
d. +9 > –9
e. –25 < –7
f. +15 > –17
Subtraction expressions:
a. (+1) – (+4) = –3
b. 0 – (+2) = –2
c. (+4) – (+1) = +3
d. 0 – (–2) = +2
e. (+4) – (–3) = +7
f. (–4) – (–3) = –1
g. (–1) – (+2) = –3
h. (–2) – (–2) = 0
i. (–1) – (+1) = –2
j. (+3) – (–3) = +6
b. 0 – (+2) = –2
c. (+4) – (+1) = +3
d. 0 – (–2) = +2
e. (+4) – (–3) = +7
f. (–4) – (–3) = –1
g. (–1) – (+2) = –3
h. (–2) – (–2) = 0
i. (–1) – (+1) = –2
j. (+3) – (–3) = +6
Page 251–252: Lift and Mineshaft Examples
Complete the expressions:
a. (+40) + 160 = +200
b. (+40) + (–240) = –200
c. (–50) + 250 = +200
d. (–50) + (–150) = –200
e. (–200) – (–40) = –160
f. (+200) – (+40) = +160
g. (–200) – (+40) = –240
b. (+40) + (–240) = –200
c. (–50) + 250 = +200
d. (–50) + (–150) = –200
e. (–200) – (–40) = –160
f. (+200) – (+40) = +160
g. (–200) – (+40) = –240
Page 253–254: Number Line Problems
1. 5 to 9?
5 + 4 = 9
2. 9 to 3?
9 + (–6) = 3
3. 3 to –2?
3 + (–5) = –2
Page 255: Evaluate using UNL (Unmarked Number Line)
a. –125 + (–30) = –155
b. +105 – (–55) = +160
c. +80 – (–150) = +230
d. –99 – (–200) = +101
b. +105 – (–55) = +160
c. +80 – (–150) = +230
d. –99 – (–200) = +101
Page 257–259: Tokens – Addition & Subtraction
1a. (+6) + (+4) = +10
1b. (–3) + (–2) = –5
1c. (+5) + (–7) = –2
1d. (–2) + (+6) = +4
1b. (–3) + (–2) = –5
1c. (+5) + (–7) = –2
1d. (–2) + (+6) = +4
2a. (+10) – (+7) = +3
2b. (–8) – (–4) = –4
2c. (–9) – (–4) = –5
2d. (+9) – (+12) = –3
2e. (–5) – (–7) = +2
2f. (–2) – (–6) = +4
2b. (–8) – (–4) = –4
2c. (–9) – (–4) = –5
2d. (+9) – (+12) = –3
2e. (–5) – (–7) = +2
2f. (–2) – (–6) = +4
Page 260: Bank Account
1. Balance = 0 + 30 + 40 + 50 – 40 – 50 – 60 = –30
2. Balance = 0 – (1+2+4+8+16+32+64+128) + 256 = –255 + 256 = +1
2. Balance = 0 – (1+2+4+8+16+32+64+128) + 256 = –255 + 256 = +1
Page 261: Heights (See diagram on page 261)
Fill heights from diagram. Highest point = 1500m, Lowest point = –1500m
Page 262–263: Temperature
Table Match:
- 14°C – 2 PM
- 8°C – 11 AM
- –2°C – 11 PM
- –4°C – 2 AM
Page 264–266: Integer Grids
Border sum of second grid:
- 5 + (–3) + (–5) = –3
- (–8) + (–2) + 7 = –3
- 5 + 0 + (–8) = –3
- (–5) + (–5) + 7 = –3
Page 265–266: Try These
• Between 0 and –7: –1, –2, –3, –4, –5, –6
• –4 and 4: –3, –2, –1, 0, 1, 2, 3
• –8 and –15: –14, –13, –12, –11, –10, –9
• –30 and –23: –29, –28, –27, –26, –25, –24
• –4 and 4: –3, –2, –1, 0, 1, 2, 3
• –8 and –15: –14, –13, –12, –11, –10, –9
• –30 and –23: –29, –28, –27, –26, –25, –24
• 8 – 13 = –5
• (–8) – (13) = –21
• (–13) – (–8) = –5
• (–13) + (–8) = –21
• 8 + (–13) = –5
• (–8) – (–13) = +5
• 13 – 8 = +5
• 13 – (–8) = +21
• (–8) – (13) = –21
• (–13) – (–8) = –5
• (–13) + (–8) = –21
• 8 + (–13) = –5
• (–8) – (–13) = +5
• 13 – 8 = +5
• 13 – (–8) = +21