Finding the Fourth Proportional to 20,688.72, 31,008.42 and 14,414.76

Step by Step Solution

1. Step 1: Write the proportion equation
   20,688.72 : 31,008.42 = 14,414.76 : x
2. Step 2: Convert to fraction form
   20,688.72/31,008.42 = 14,414.76/x
3. Step 3: Cross multiply
   20,688.72x = 31,008.42 × 14,414.76
4. Step 4: Simplify right side
   20,688.72x = 446,978,932.28
5. Step 5: Solve for x
   x = 446,978,932.28/20,688.72
6. Step 6: Final answer
   x = 21,604.96