Adding and Subtracting Integers — Worksheet & Memo

∑ DANEMATHICS

FREE CAPS MATHS RESOURCES

Grade 8 · Integers

Adding and Subtracting Integers

MEMORANDUM

Name:

Class:

Date:

Mark

/ 13

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
(1)
−7 < −3 (−7 is further left)✓ (1)
3
(−8) + (−5)
(1)
Same signs → 8 + 5 = 13 → −13✓ (1)
4
(−12) + 7
(1)
Different signs → 12 − 7 = 5, bigger is negative → −5✓ (1)
5
15 + (−20)
(1)
Different signs → 20 − 15 = 5, bigger is negative → −5✓ (1)
6
6 − (−9)
(1)
6 + 9 = 15✓ (1)
7
(−4) − 7
(1)
−4 + (−7) = −11✓ (1)
8
(−7) − (−10)
(1)
−7 + 10 = 3✓ (1)
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 position?
(2)
−120 + 45 = −75 m (75 m below the surface)✓✓ (2)

TOTAL: 13 marks