Finding the Fourth Proportional to 439,256.59, 658,933.31 and 139,667.09

Step by Step Solution

1. Step 1: Write the proportion equation
   439,256.59 : 658,933.31 = 139,667.09 : x
2. Step 2: Convert to fraction form
   439,256.59/658,933.31 = 139,667.09/x
3. Step 3: Cross multiply
   439,256.59x = 658,933.31 × 139,667.09
4. Step 4: Simplify right side
   439,256.59x = 92,031,294,966.27
5. Step 5: Solve for x
   x = 92,031,294,966.27/439,256.59
6. Step 6: Final answer
   x = 209,516.03