Finding the Fourth Proportional to 115,728.52, 173,414.16 and 78,141.28

Step by Step Solution

1. Step 1: Write the proportion equation
   115,728.52 : 173,414.16 = 78,141.28 : x
2. Step 2: Convert to fraction form
   115,728.52/173,414.16 = 78,141.28/x
3. Step 3: Cross multiply
   115,728.52x = 173,414.16 × 78,141.28
4. Step 4: Simplify right side
   115,728.52x = 13,550,804,432.52
5. Step 5: Solve for x
   x = 13,550,804,432.52/115,728.52
6. Step 6: Final answer
   x = 117,091.31