Adding and Subtracting Integers — Worksheet & Memo

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Grade 8 · Integers

Adding and Subtracting Integers

MEMORANDUM

Name:

Class:

Date:

Mark

/ 20

Answer all questions. Show all your working — marks are awarded for method as well as the final answer. Teacher copy: accept any correct equivalent method.

1
Arrange in ascending order: −4, 6, −9, 0, 2
(2)
−9, −4, 0, 2, 6✓✓ (2)
2
Fill in < or >: −7 ___ −3
(2)
−7 < −3 (−7 is further left)✓✓ (2)
3
(−8) + (−5)
(2)
Same signs → 8+5 = 13 → −13✓✓ (2)
4
(−12) + 7
(2)
Different signs → 12−7 = 5, bigger is negative → −5✓✓ (2)
5
15 + (−20)
(2)
Different signs → 20−15 = 5, bigger is negative → −5✓✓ (2)
6
6 − (−9)
(2)
6 + 9 = 15✓✓ (2)
7
(−4) − 7
(2)
−4 + (−7) = −11✓✓ (2)
8
(−7) − (−10)
(2)
−7 + 10 = 3✓✓ (2)
9
The temperature is −6 °C and rises by 4 °C. What is the new temperature?
(2)
−6 + 4 = −2 °C✓✓ (2)
10
A submarine at −120 m rises 45 m. What is its new depth?
(2)
−120 + 45 = −75 m✓✓ (2)

TOTAL: 20 marks