Finding the Fourth Proportional to 21,838.29, 30,139.35 and 12,148.71

Step by Step Solution

1. Step 1: Write the proportion equation
   21,838.29 : 30,139.35 = 12,148.71 : x
2. Step 2: Convert to fraction form
   21,838.29/30,139.35 = 12,148.71/x
3. Step 3: Cross multiply
   21,838.29x = 30,139.35 × 12,148.71
4. Step 4: Simplify right side
   21,838.29x = 366,154,222.74
5. Step 5: Solve for x
   x = 366,154,222.74/21,838.29
6. Step 6: Final answer
   x = 16,766.62