Write the following as decimal `:`
Twenty and five-tenths.

Answer

To convert "Twenty and five-tenths" into decimal form, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Whole Number**:
- The phrase "Twenty" represents the whole number 20.

2. **Identify the Decimal Part**:
- The phrase "five-tenths" indicates a decimal fraction. The term "tenths" means that the number is in the first decimal place. Therefore, "five-tenths" can be written as 0.5.

3. **Combine the Whole Number and the Decimal**:
- Now, we combine the whole number (20) with the decimal part (0.5). This can be done by adding them together:
\[ 20 + 0.5 = 20.5 \]

4. **Final Result**:
- Thus, "Twenty and five-tenths" as a decimal is **20.5**.

### Summary:
- The decimal representation of "Twenty and five-tenths" is **20.5**.