Finding the Fourth Proportional to 12,399.89, 18,576.38 and 9,612.91

Step by Step Solution

1. Step 1: Write the proportion equation
   12,399.89 : 18,576.38 = 9,612.91 : x
2. Step 2: Convert to fraction form
   12,399.89/18,576.38 = 9,612.91/x
3. Step 3: Cross multiply
   12,399.89x = 18,576.38 × 9,612.91
4. Step 4: Simplify right side
   12,399.89x = 178,573,069.07
5. Step 5: Solve for x
   x = 178,573,069.07/12,399.89
6. Step 6: Final answer
   x = 14,401.18