Finding the Fourth Proportional to 12,389.43, 18,589.59 and 5,815.05

Step by Step Solution

1. Step 1: Write the proportion equation
   12,389.43 : 18,589.59 = 5,815.05 : x
2. Step 2: Convert to fraction form
   12,389.43/18,589.59 = 5,815.05/x
3. Step 3: Cross multiply
   12,389.43x = 18,589.59 × 5,815.05
4. Step 4: Simplify right side
   12,389.43x = 108,099,395.33
5. Step 5: Solve for x
   x = 108,099,395.33/12,389.43
6. Step 6: Final answer
   x = 8,725.13