Mastery Q 1.2

Mastery 1.2

1. By using a number line, f ind the sum of each of the following:
(a) 7 + (– 6) + (–1) =
(b) – 6 + (–2) + 9 =
(c) –2 + (–3) + (–5) =

2. Solve each of the following:
(a) –13 + (–8) + (+1)
(b) –28 + (–11) – (–12)
(c) – 40 – (–19) + (–33)

3. Evaluate each of the following:

(a) – 4 + 6 – (–8)

(b) 336 + (–128) ÷ 4

(c) 12 × 5 – (–21)

(d) (–8) × (– 4)
(–8) – (– 4)

(e) –18 + (–11) – (–10) – 15

(f) 64 – (–2) × 32 ÷ (–8)

4. Fill in the blanks with suitable integers:
(a) 3, 1, –1,  ,  , –7
(b) –8, –5,  ,  , 4,
(c) –2, – 4, –8,  ,  , – 64,
(d) 1, 3,  ,  ,  , 243, 729
(e) – 60, – 48,  ,  ,  , 0,
(f) 0, 1, 4,  , 16,  ,  ,

5. –22, –17, –12, p, –2, q, …
Based on the list of numbers, f ind the value of p + q.

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6. A company makes a profit of RM6 200 in June. The company then incurs a loss of
RM2 500 and RM3 900 in July and August respectively. Calculate the company’s
total profit or loss in these three months.

7. Round I II III

Marks 5 –2 3

The table shows the marks obtained by Zainab in a quiz competition for three rounds.
Calculate the total marks Zainab obtained in the competition.

8. A solution with a temperature of –2°C was taken out from a refrigerator. The
temperature of the solution rose by 15°C after leaving it on a table for 20 minutes.
Then, the solution was put back into the refrigerator and the temperature was found
to drop by 18°C after 1 hour. Calculate the final temperature of the solution.

9. 2 m every second

P

A particle moves in the direction of the arrow as shown in the diagram above. If the
particle is at P now, f ind the distance of the particle from P 10 seconds before.

10. The water level in a leaking tank drops 25 mm every minute. If the water level in the
tank is 220 cm now, calculate the water level, in cm, in the tank after 30 minutes.

1 1. The initial temperature of a cup of coffee is 78°C. The temperature of the coffee
becomes 54°C after 6 minutes. If the drop in temperature of the coffee is the same
every minute, find the temperature change of the coffee in one minute.

12. A helicopter descends 2 km within x minutes. If the helicopter descends 100 m every
minute, calculate the value of x.

1 3. In a quiz, a participant is required to answer 5 questions. A score of 4 marks will be
given for each correct answer and 2 marks will be deducted for each incorrect answer.
If a participant answers 3 questions correctly, what is the total mark obtained?

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Answers

1. (a) 0

–1 0 1 2 3 4 5 6 7
(b) 1

–8 –7 –6 –5 –4 –3 –2 –1 0 1
(c) –10

–10 –9 –8 –7 –6 –5 – 4 –3 –2 –1 0
2. (a) –20

(b) –27
(c) –54
3. (a) 10
(b) 304
(c) 81
(d) –8
(e) –34
(f) 56
4. (a) –3, –5
(b) –2, 1, 7
(c) –16, –32, –128
(d) 9, 27, 81
(e) –36, –24, –12, 12
(f) 9, 25, 36, 49
5. – 4
6. A loss of RM200

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7. 6 marks
8. –5°C
9. 20 m to the left of point P
10. 145 cm
11. Drop 4°C every minute
12. 20
13. 8 marks

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