Finding the Fourth Proportional to 431,818.79, 646,860.71 and 215,024.38

Step by Step Solution

1. Step 1: Write the proportion equation
   431,818.79 : 646,860.71 = 215,024.38 : x
2. Step 2: Convert to fraction form
   431,818.79/646,860.71 = 215,024.38/x
3. Step 3: Cross multiply
   431,818.79x = 646,860.71 × 215,024.38
4. Step 4: Simplify right side
   431,818.79x = 139,090,822,034.52
5. Step 5: Solve for x
   x = 139,090,822,034.52/431,818.79
6. Step 6: Final answer
   x = 322,104.61