Finding the Fourth Proportional to 12,406.72, 18,609.36 and 3,172

Step by Step Solution

1. Step 1: Write the proportion equation
   12,406.72 : 18,609.36 = 3,172 : x
2. Step 2: Convert to fraction form
   12,406.72/18,609.36 = 3,172/x
3. Step 3: Cross multiply
   12,406.72x = 18,609.36 × 3,172
4. Step 4: Simplify right side
   12,406.72x = 59,028,889.92
5. Step 5: Solve for x
   x = 59,028,889.92/12,406.72
6. Step 6: Final answer
   x = 4,757.82