Finding the Fourth Proportional to 21,022.57, 31,553.54 and 10,641.61

Step by Step Solution

1. Step 1: Write the proportion equation
   21,022.57 : 31,553.54 = 10,641.61 : x
2. Step 2: Convert to fraction form
   21,022.57/31,553.54 = 10,641.61/x
3. Step 3: Cross multiply
   21,022.57x = 31,553.54 × 10,641.61
4. Step 4: Simplify right side
   21,022.57x = 335,780,413.59
5. Step 5: Solve for x
   x = 335,780,413.59/21,022.57
6. Step 6: Final answer
   x = 15,972.38