Finding the Fourth Proportional to 16,821.24, 23,208.42 and 10,856.40

Step by Step Solution

1. Step 1: Write the proportion equation
   16,821.24 : 23,208.42 = 10,856.40 : x
2. Step 2: Convert to fraction form
   16,821.24/23,208.42 = 10,856.40/x
3. Step 3: Cross multiply
   16,821.24x = 23,208.42 × 10,856.40
4. Step 4: Simplify right side
   16,821.24x = 251,959,890.89
5. Step 5: Solve for x
   x = 251,959,890.89/16,821.24
6. Step 6: Final answer
   x = 14,978.68