If x, 20, 30, and 60 are in proportion, then what is the value of x?

Answer

To find the value of \( x \) when \( x, 20, 30, \) and \( 60 \) are in proportion, we can set up the proportion as follows:

1. **Set up the proportion**:
\[ \frac{x}{20} = \frac{30}{60} \]

2. **Simplify the right side**:
\[ \frac{30}{60} = \frac{1}{2} \]
So, we can rewrite the equation as:
\[ \frac{x}{20} = \frac{1}{2} \]

3. **Cross multiply**:
\[ x \cdot 2 = 20 \cdot 1 \]
This simplifies to:
\[ 2x = 20 \]

4. **Solve for \( x \)**:
Divide both sides by 2:
\[ x = \frac{20}{2} = 10 \]

Thus, the value of \( x \) is \( 10 \).