Finding the Fourth Proportional to 21,908.14, 30,234.81 and 12,477.31

Step by Step Solution

1. Step 1: Write the proportion equation
   21,908.14 : 30,234.81 = 12,477.31 : x
2. Step 2: Convert to fraction form
   21,908.14/30,234.81 = 12,477.31/x
3. Step 3: Cross multiply
   21,908.14x = 30,234.81 × 12,477.31
4. Step 4: Simplify right side
   21,908.14x = 377,249,097.16
5. Step 5: Solve for x
   x = 377,249,097.16/21,908.14
6. Step 6: Final answer
   x = 17,219.59