The number of significant figures in 0.00030 is……………………

Answer

To determine the number of significant figures in the number 0.00030, we can follow these steps:

### Step-by-Step Solution:

1. **Identify Non-Zero Digits**:
- Non-zero digits are always considered significant. In the number 0.00030, the digit '3' is a non-zero digit.
- **Significant Figures So Far**: 1 (the digit '3').

2. **Identify Zeros**:
- According to the rules of significant figures, leading zeros (zeros before the first non-zero digit) are not significant. In this case, the three zeros before '3' (0.0003) are leading zeros and do not count.
- **Significant Figures So Far**: Still 1.

3. **Trailing Zeros in Decimal Portion**:
- The zero after '3' (in 0.00030) is a trailing zero in the decimal portion. According to the rules, trailing zeros in a decimal number are significant.
- **Significant Figures Now**: 2 (the digit '3' and the trailing zero).

4. **Final Count**:
- Therefore, the total number of significant figures in the number 0.00030 is 2.

### Final Answer:
The number of significant figures in 0.00030 is **2**.

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