Finding the Fourth Proportional to 85,789.78, 128,542.41 and 60,705.49

Step by Step Solution

1. Step 1: Write the proportion equation
   85,789.78 : 128,542.41 = 60,705.49 : x
2. Step 2: Convert to fraction form
   85,789.78/128,542.41 = 60,705.49/x
3. Step 3: Cross multiply
   85,789.78x = 128,542.41 × 60,705.49
4. Step 4: Simplify right side
   85,789.78x = 7,803,229,984.83
5. Step 5: Solve for x
   x = 7,803,229,984.83/85,789.78
6. Step 6: Final answer
   x = 90,957.57