Finding the Fourth Proportional to 432,863.30, 648,128.55 and 339,551.30

Step by Step Solution

1. Step 1: Write the proportion equation
   432,863.30 : 648,128.55 = 339,551.30 : x
2. Step 2: Convert to fraction form
   432,863.30/648,128.55 = 339,551.30/x
3. Step 3: Cross multiply
   432,863.30x = 648,128.55 × 339,551.30
4. Step 4: Simplify right side
   432,863.30x = 220,072,891,719.62
5. Step 5: Solve for x
   x = 220,072,891,719.62/432,863.30
6. Step 6: Final answer
   x = 508,411.99