Let's solve each problem step by step using the
counter method for adding negative numbers. The key idea is:
-
Red counters represent
negative numbers (–1 each).
-
Yellow counters represent
positive numbers (+1 each).
- A
zero-pair is a red and yellow counter together (–1 + 1 = 0). We can remove zero-pairs because they cancel out.
- After removing all zero-pairs, the remaining counters give the answer.
---
Example Recap: –5 + 3
- 5 red counters (–5) + 3 yellow counters (+3)
- Form 3 zero-pairs (3 red + 3 yellow), cross them out
- Left with 2 red counters → Answer:
–2
---
Now let’s solve each problem.
---
a) –4 + 2
- Start with:
- 4 red counters (–4)
- 2 yellow counters (+2)
```
Red: [–] [–] [–] [–]
Yellow: [+] [+]
```
- Make zero-pairs: Pair 2 red with 2 yellow → 2 zero-pairs
- Remove them
Remaining: 2 red counters
✔ Answer: –2
---
b) –4 + 3
- 4 red counters (–4)
- 3 yellow counters (+3)
```
Red: [–] [–] [–] [–]
Yellow: [+] [+] [+]
```
- Make 3 zero-pairs (3 red + 3 yellow) → remove them
- Remaining: 1 red counter
✔ Answer: –1
---
c) –4 + 4
- 4 red counters (–4)
- 4 yellow counters (+4)
```
Red: [–] [–] [–] [–]
Yellow: [+] [+] [+] [+]
```
- Make 4 zero-pairs → remove all
- No counters left
✔ Answer: 0
---
d) –4 + 5
- 4 red counters (–4)
- 5 yellow counters (+5)
```
Red: [–] [–] [–] [–]
Yellow: [+] [+] [+] [+] [+]
```
- Make 4 zero-pairs → remove 4 red and 4 yellow
- Remaining: 1 yellow counter
✔ Answer: +1
---
✔ Final Answers:
a)
–2
b)
–1
c)
0
d)
+1
You would fill in the answers in the boxes as shown on the worksheet.
Parent Tip: Review the logic above to help your child master the concept of zero pairs worksheet.
