Finding the Fourth Proportional to 8,863.28, 12,231.20 and 5,280.72

Step by Step Solution

1. Step 1: Write the proportion equation
   8,863.28 : 12,231.20 = 5,280.72 : x
2. Step 2: Convert to fraction form
   8,863.28/12,231.20 = 5,280.72/x
3. Step 3: Cross multiply
   8,863.28x = 12,231.20 × 5,280.72
4. Step 4: Simplify right side
   8,863.28x = 64,589,542.46
5. Step 5: Solve for x
   x = 64,589,542.46/8,863.28
6. Step 6: Final answer
   x = 7,287.32