Finding the Fourth Proportional to 85,542.72, 128,789.52 and 74,112

Step by Step Solution

1. Step 1: Write the proportion equation
   85,542.72 : 128,789.52 = 74,112 : x
2. Step 2: Convert to fraction form
   85,542.72/128,789.52 = 74,112/x
3. Step 3: Cross multiply
   85,542.72x = 128,789.52 × 74,112
4. Step 4: Simplify right side
   85,542.72x = 9,544,848,906.24
5. Step 5: Solve for x
   x = 9,544,848,906.24/85,542.72
6. Step 6: Final answer
   x = 111,579.91