Finding the Fourth Proportional to 10,728.47, 14,797.13 and 9,399.86

Step by Step Solution

1. Step 1: Write the proportion equation
   10,728.47 : 14,797.13 = 9,399.86 : x
2. Step 2: Convert to fraction form
   10,728.47/14,797.13 = 9,399.86/x
3. Step 3: Cross multiply
   10,728.47x = 14,797.13 × 9,399.86
4. Step 4: Simplify right side
   10,728.47x = 139,090,950.40
5. Step 5: Solve for x
   x = 139,090,950.40/10,728.47
6. Step 6: Final answer
   x = 12,964.66