Finding the Fourth Proportional to 22,087.31, 30,470.42 and 13,129.71

Step by Step Solution

1. Step 1: Write the proportion equation
   22,087.31 : 30,470.42 = 13,129.71 : x
2. Step 2: Convert to fraction form
   22,087.31/30,470.42 = 13,129.71/x
3. Step 3: Cross multiply
   22,087.31x = 30,470.42 × 13,129.71
4. Step 4: Simplify right side
   22,087.31x = 400,067,712.53
5. Step 5: Solve for x
   x = 400,067,712.53/22,087.31
6. Step 6: Final answer
   x = 18,113.02