Finding the Fourth Proportional to 405,139.16, 558,978.18 and 233,048.18

Step by Step Solution

1. Step 1: Write the proportion equation
   405,139.16 : 558,978.18 = 233,048.18 : x
2. Step 2: Convert to fraction form
   405,139.16/558,978.18 = 233,048.18/x
3. Step 3: Cross multiply
   405,139.16x = 558,978.18 × 233,048.18
4. Step 4: Simplify right side
   405,139.16x = 130,268,847,508.71
5. Step 5: Solve for x
   x = 130,268,847,508.71/405,139.16
6. Step 6: Final answer
   x = 321,540.99