Explanation:

- The original equation: 11 + 4 - 3 ÷ 3 × 7 = 8

- Objective: Find the interchange of signs that makes the equation true.

Option 1: × and ÷

- Changes equation to: 11 + 4 - 3 × 3 ÷ 7

- This does not equal 8.

Option 2: + and ÷

- Changes equation to: 11 ÷ 4 - 3 + 3 × 7

- This does not equal 8.

Option 3: - and ×

- Changes equation to: 11 + 4 × 3 ÷ 3 - 7

- Simplifies to: 11 + 4 - 7 = 8

- This equals 8.

Option 4: + and ×

- Changes equation to: 11 × 4 - 3 ÷ 3 + 7

- This does not equal 8.

- Correct Answer: Option 3

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