Finding the Fourth Proportional to 21,818.82, 30,107.81 and 12,387.30

Step by Step Solution

1. Step 1: Write the proportion equation
   21,818.82 : 30,107.81 = 12,387.30 : x
2. Step 2: Convert to fraction form
   21,818.82/30,107.81 = 12,387.30/x
3. Step 3: Cross multiply
   21,818.82x = 30,107.81 × 12,387.30
4. Step 4: Simplify right side
   21,818.82x = 372,954,474.81
5. Step 5: Solve for x
   x = 372,954,474.81/21,818.82
6. Step 6: Final answer
   x = 17,093.25