Finding the Fourth Proportional to 394,978.02, 592,353.90 and 128,761.80

Step by Step Solution

1. Step 1: Write the proportion equation
   394,978.02 : 592,353.90 = 128,761.80 : x
2. Step 2: Convert to fraction form
   394,978.02/592,353.90 = 128,761.80/x
3. Step 3: Cross multiply
   394,978.02x = 592,353.90 × 128,761.80
4. Step 4: Simplify right side
   394,978.02x = 76,272,554,401.02
5. Step 5: Solve for x
   x = 76,272,554,401.02/394,978.02
6. Step 6: Final answer
   x = 193,105.82