The ……….. Error are those which occur ……… by …………. .

Answer

To fill in the blanks in the statement "The ……….. Error are those which occur ……… by ………….," we need to identify the type of error and its characteristics.

1. **Identify the Type of Error**:
- We have three types of errors: random error, systematic error, and gross error.
- The question is asking for a specific type of error that occurs in a particular manner.

2. **Understanding Random Error**:
- Random errors are those that occur by chance and are unpredictable. They can arise from various sources, such as fluctuations in the measurement process or environmental conditions.

3. **Fill in the Blanks**:
- The first blank should be filled with "Random" to indicate the type of error.
- The second blank should be filled with "chance" to describe how these errors occur.
- The third blank can be filled with "irregularity" to emphasize the unpredictable nature of these errors.

Thus, the completed statement is:
"The **Random** Error are those which occur **by chance**."

### Step-by-Step Solution:
1. Identify the types of errors: random, systematic, and gross.
2. Understand the characteristics of random errors.
3. Fill in the first blank with "Random".
4. Fill in the second blank with "chance".
5. Fill in the third blank with "irregularity".