Use the appropriate symbol `=,lt` or `gt` to fill the following blanks : `3xx7…31-9`.

Answer

To solve the question "Use the appropriate symbol `=, <, or >` to fill the following blanks: `3 x 7 ___ 31 - 9`", we will follow these steps:

### Step 1: Calculate \(3 \times 7\)
First, we need to calculate the left side of the inequality:
\[ 3 \times 7 = 21 \]

### Step 2: Calculate \(31 - 9\)
Next, we calculate the right side of the inequality:
\[ 31 - 9 = 22 \]

### Step 3: Compare the two results
Now we have:
\[ 21 \quad \_\_\_ \quad 22 \]
We need to determine the relationship between 21 and 22.

### Step 4: Determine the appropriate symbol
Since \(21\) is less than \(22\), we use the symbol `<` to fill in the blank:
\[ 3 \times 7 < 31 - 9 \]

### Final Answer
The completed inequality is:
\[ 3 \times 7 < 31 - 9 \]

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