Write each of the following statements in equation:
20 decreased by a number x is equal to 15

Answer

To convert the statement "20 decreased by a number x is equal to 15" into an equation, follow these steps:

### Step-by-Step Solution:

1. **Identify the components of the statement**:
- The phrase "20 decreased by a number x" indicates that we are starting with 20 and subtracting x from it.
- The phrase "is equal to 15" indicates that the result of the subtraction is equal to 15.

2. **Translate the phrase into mathematical terms**:
- "20 decreased by a number x" can be expressed as \( 20 - x \).
- The phrase "is equal to" translates to the equal sign \( = \).
- Finally, we have the number 15.

3. **Combine the components into an equation**:
- Putting it all together, we write the equation as:
\[ 20 - x = 15 \]

### Final Equation:
\[ 20 - x = 15 \]

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