Finding the Fourth Proportional to 8,321.60, 12,391.82 and 8,229.57

Step by Step Solution

1. Step 1: Write the proportion equation
   8,321.60 : 12,391.82 = 8,229.57 : x
2. Step 2: Convert to fraction form
   8,321.60/12,391.82 = 8,229.57/x
3. Step 3: Cross multiply
   8,321.60x = 12,391.82 × 8,229.57
4. Step 4: Simplify right side
   8,321.60x = 101,979,308.97
5. Step 5: Solve for x
   x = 101,979,308.97/8,321.60
6. Step 6: Final answer
   x = 12,254.78