Physical quantity = __________ X unit.

Answer

To solve the question "Physical quantity = __________ X unit," we can break it down into clear steps:

### Step-by-Step Solution:

1. **Understanding Physical Quantity**: A physical quantity is a property of a physical system that can be measured. Examples include mass, length, time, and volume.

2. **Identifying Components**: A physical quantity can be expressed in terms of two components:
- **Numerical Value**: This is the number that represents the magnitude of the physical quantity.
- **Unit**: This is the standard measurement used to express the physical quantity (e.g., kilograms for mass, meters for length).

3. **Formulating the Expression**: The relationship can be expressed as:
\[ \text{Physical Quantity} = \text{Numerical Value} \times \text{Unit} \]

4. **Examples**:
- If you buy 5 kg of sugar, "5" is the numerical value and "kg" (kilograms) is the unit.
- If you measure 500 ml of milk, "500" is the numerical value and "ml" (milliliters) is the unit.

5. **Final Answer**: Therefore, we can fill in the blank in the original question:
\[ \text{Physical quantity} = \text{Numerical Value} \times \text{Unit} \]

### Final Answer:
Physical quantity = Numerical Value X Unit.

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