Finding the Fourth Proportional to 129,378.89, 178,542.83 and 72,016.96

Step by Step Solution

1. Step 1: Write the proportion equation
   129,378.89 : 178,542.83 = 72,016.96 : x
2. Step 2: Convert to fraction form
   129,378.89/178,542.83 = 72,016.96/x
3. Step 3: Cross multiply
   129,378.89x = 178,542.83 × 72,016.96
4. Step 4: Simplify right side
   129,378.89x = 12,858,111,932.67
5. Step 5: Solve for x
   x = 12,858,111,932.67/129,378.89
6. Step 6: Final answer
   x = 99,383.39