Finding the Fourth Proportional to 21,831.75, 30,132.68 and 13,872.42

Step by Step Solution

1. Step 1: Write the proportion equation
   21,831.75 : 30,132.68 = 13,872.42 : x
2. Step 2: Convert to fraction form
   21,831.75/30,132.68 = 13,872.42/x
3. Step 3: Cross multiply
   21,831.75x = 30,132.68 × 13,872.42
4. Step 4: Simplify right side
   21,831.75x = 418,013,123.32
5. Step 5: Solve for x
   x = 418,013,123.32/21,831.75
6. Step 6: Final answer
   x = 19,147.03