Finding the Fourth Proportional to 21,616.72, 29,831.53 and 12,185.28

Step by Step Solution

1. Step 1: Write the proportion equation
   21,616.72 : 29,831.53 = 12,185.28 : x
2. Step 2: Convert to fraction form
   21,616.72/29,831.53 = 12,185.28/x
3. Step 3: Cross multiply
   21,616.72x = 29,831.53 × 12,185.28
4. Step 4: Simplify right side
   21,616.72x = 363,505,545.88
5. Step 5: Solve for x
   x = 363,505,545.88/21,616.72
6. Step 6: Final answer
   x = 16,815.94