What is error of measurement ?

Explanation

### Step-by-Step Solution:

1. **Definition of Measurement Error**:
The error of measurement refers to the discrepancy between the value that is measured and the actual or true value of the quantity being measured.

2. **Understanding Observed and True Values**:
- The **observed value** is the value that you obtain from your measurement.
- The **true value** is the actual value that is accepted as correct, which can be determined through precise methods or standards.
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