Finding the Fourth Proportional to 128,139.47, 176,831.82 and 71,550.86

Step by Step Solution

1. Step 1: Write the proportion equation
   128,139.47 : 176,831.82 = 71,550.86 : x
2. Step 2: Convert to fraction form
   128,139.47/176,831.82 = 71,550.86/x
3. Step 3: Cross multiply
   128,139.47x = 176,831.82 × 71,550.86
4. Step 4: Simplify right side
   128,139.47x = 12,652,468,796.37
5. Step 5: Solve for x
   x = 12,652,468,796.37/128,139.47
6. Step 6: Final answer
   x = 98,739.82