Finding the Fourth Proportional to 8,939.01, 12,339.81 and 5,581.20

Step by Step Solution

1. Step 1: Write the proportion equation
   8,939.01 : 12,339.81 = 5,581.20 : x
2. Step 2: Convert to fraction form
   8,939.01/12,339.81 = 5,581.20/x
3. Step 3: Cross multiply
   8,939.01x = 12,339.81 × 5,581.20
4. Step 4: Simplify right side
   8,939.01x = 68,870,947.57
5. Step 5: Solve for x
   x = 68,870,947.57/8,939.01
6. Step 6: Final answer
   x = 7,704.54