Finding the Fourth Proportional to 21,162.72, 31,711.20 and 8,007.96

Step by Step Solution

1. Step 1: Write the proportion equation
   21,162.72 : 31,711.20 = 8,007.96 : x
2. Step 2: Convert to fraction form
   21,162.72/31,711.20 = 8,007.96/x
3. Step 3: Cross multiply
   21,162.72x = 31,711.20 × 8,007.96
4. Step 4: Simplify right side
   21,162.72x = 253,942,021.15
5. Step 5: Solve for x
   x = 253,942,021.15/21,162.72
6. Step 6: Final answer
   x = 11,999.50