Finding the Fourth Proportional to 21,616.39, 29,833.17 and 12,057.78

Step by Step Solution

1. Step 1: Write the proportion equation
   21,616.39 : 29,833.17 = 12,057.78 : x
2. Step 2: Convert to fraction form
   21,616.39/29,833.17 = 12,057.78/x
3. Step 3: Cross multiply
   21,616.39x = 29,833.17 × 12,057.78
4. Step 4: Simplify right side
   21,616.39x = 359,721,800.56
5. Step 5: Solve for x
   x = 359,721,800.56/21,616.39
6. Step 6: Final answer
   x = 16,641.16