Finding the Fourth Proportional to 8,728.79, 13,093.33 and 8,285.72

Step by Step Solution

1. Step 1: Write the proportion equation
   8,728.79 : 13,093.33 = 8,285.72 : x
2. Step 2: Convert to fraction form
   8,728.79/13,093.33 = 8,285.72/x
3. Step 3: Cross multiply
   8,728.79x = 13,093.33 × 8,285.72
4. Step 4: Simplify right side
   8,728.79x = 108,487,624.82
5. Step 5: Solve for x
   x = 108,487,624.82/8,728.79
6. Step 6: Final answer
   x = 12,428.71