🔍 Part 1: Operation Detective Work

Instructions: Look at each number sentence carefully. Work out which operation (+, −, ×, ÷) is missing to make the equation true. Remember: the equals sign means "the same as"!

1. 298 ___ 127 = 171

Missing operation: ___________

2. 84 ___ 12 = 72

Missing operation: ___________

3. 15 ___ 6 = 90

Missing operation: ___________

4. 144 ___ 12 = 12

Missing operation: ___________

🎯 Part 2: Multiple Choice Detective

Instructions: Circle the correct missing operation for each number sentence.

5. 56 ___ 8 = 7

+

−

×

÷

6. 245 ___ 89 = 156

+

−

×

÷

7. 37 ___ 28 = 65

+

−

×

÷

🧠 Part 3: Detective Reasoning

Instructions: For each problem, explain your thinking. How did you work out the missing operation?

8. 72 ___ 9 = 8

Missing operation: ___________

My reasoning:

9. 123 ___ 77 = 200

Missing operation: ___________

My reasoning:

🔧 Part 4: Detective Tools

Instructions: Match each strategy with when you might use it to find a missing operation.

10. Match the detective strategy with its use:

1. Estimation

2. Inverse operations

3. Number patterns

4. Calculator check

A. To verify your answer is correct

B. To get a rough idea of the answer size

C. To work backwards from the answer

D. To spot if numbers increase or decrease

⭐ Part 5: Challenge Detective Cases

Instructions: These are tricky cases! Use all your detective skills.

11. 156 ___ 13 = 12

Missing operation: ___________

Show your working:

12. 25 ___ 4 = 100

Missing operation: ___________

Show your working:

13. Create your own missing operation problem:

_____ ___ _____ = _____

Ask a classmate to solve it!

📝 Part 6: Detective Reflection

14. What strategies helped you most when finding missing operations? Tick all that apply:

Estimating the answer first

Using inverse operations

Checking if the number gets bigger or smaller

Using a calculator to check

Thinking about what makes sense

15. Complete this sentence:

The equals sign (=) means ________________________________

16. Write one tip you would give to another student about finding missing operations:

Missing Operation Detective

Missing Operation Detective

🔍 Part 1: Operation Detective Work

🎯 Part 2: Multiple Choice Detective

🧠 Part 3: Detective Reasoning

🔧 Part 4: Detective Tools

⭐ Part 5: Challenge Detective Cases

📝 Part 6: Detective Reflection

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