Finding the Fourth Proportional to 120,208.27, 165,831.56 and 77,780.47

Step by Step Solution

1. Step 1: Write the proportion equation
   120,208.27 : 165,831.56 = 77,780.47 : x
2. Step 2: Convert to fraction form
   120,208.27/165,831.56 = 77,780.47/x
3. Step 3: Cross multiply
   120,208.27x = 165,831.56 × 77,780.47
4. Step 4: Simplify right side
   120,208.27x = 12,898,456,288.73
5. Step 5: Solve for x
   x = 12,898,456,288.73/120,208.27
6. Step 6: Final answer
   x = 107,300.91