Finding the Fourth Proportional to 388,520.98, 582,885.18 and 139,228.18

Step by Step Solution

1. Step 1: Write the proportion equation
   388,520.98 : 582,885.18 = 139,228.18 : x
2. Step 2: Convert to fraction form
   388,520.98/582,885.18 = 139,228.18/x
3. Step 3: Cross multiply
   388,520.98x = 582,885.18 × 139,228.18
4. Step 4: Simplify right side
   388,520.98x = 81,154,042,760.37
5. Step 5: Solve for x
   x = 81,154,042,760.37/388,520.98
6. Step 6: Final answer
   x = 208,879.43