What is the fourth proportional to 14, 6, 28?

Options

A. 12
B. 3
C. 7
D. 6

Answer

To find the fourth proportional to the numbers 14, 6, and 28, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Fourth Proportional**:
The fourth proportional to three numbers A, B, and C is a number D such that the ratio of A to B is the same as the ratio of C to D. This can be expressed mathematically as:
\[ \frac{A}{B} = \frac{C}{D} \]

2. **Set Up the Equation**:
Rearranging the above equation gives us:
\[ D = \frac{B \times C}{A} \]

3. **Substitute the Given Values**:
Here, we have A = 14, B = 6, and C = 28. Plugging these values into the equation gives:
\[ D = \frac{6 \times 28}{14} \]

4. **Calculate the Multiplication**:
First, calculate \(6 \times 28\):
\[ 6 \times 28 = 168 \]

5. **Divide by A**:
Now, divide this result by 14:
\[ D = \frac{168}{14} \]

6. **Perform the Division**:
Calculate \(168 \div 14\):
\[ 168 \div 14 = 12 \]

7. **Conclusion**:
Therefore, the fourth proportional to 14, 6, and 28 is:
\[ \boxed{12} \]