Finding the Fourth Proportional to 309,216.89, 463,501.61 and 129,405.34

Step by Step Solution

1. Step 1: Write the proportion equation
   309,216.89 : 463,501.61 = 129,405.34 : x
2. Step 2: Convert to fraction form
   309,216.89/463,501.61 = 129,405.34/x
3. Step 3: Cross multiply
   309,216.89x = 463,501.61 × 129,405.34
4. Step 4: Simplify right side
   309,216.89x = 59,979,583,432.60
5. Step 5: Solve for x
   x = 59,979,583,432.60/309,216.89
6. Step 6: Final answer
   x = 193,972.53