Finding the Fourth Proportional to 21,816.78, 30,108.33 and 12,869.52

Step by Step Solution

1. Step 1: Write the proportion equation
   21,816.78 : 30,108.33 = 12,869.52 : x
2. Step 2: Convert to fraction form
   21,816.78/30,108.33 = 12,869.52/x
3. Step 3: Cross multiply
   21,816.78x = 30,108.33 × 12,869.52
4. Step 4: Simplify right side
   21,816.78x = 387,479,755.10
5. Step 5: Solve for x
   x = 387,479,755.10/21,816.78
6. Step 6: Final answer
   x = 17,760.63