Finding the Fourth Proportional to 23,115.31, 31,898.81 and 12,906.50

Step by Step Solution

1. Step 1: Write the proportion equation
   23,115.31 : 31,898.81 = 12,906.50 : x
2. Step 2: Convert to fraction form
   23,115.31/31,898.81 = 12,906.50/x
3. Step 3: Cross multiply
   23,115.31x = 31,898.81 × 12,906.50
4. Step 4: Simplify right side
   23,115.31x = 411,701,831.77
5. Step 5: Solve for x
   x = 411,701,831.77/23,115.31
6. Step 6: Final answer
   x = 17,810.79