Finding the Fourth Proportional to 642,111.52, 886,120.42 and 387,413.50

Step by Step Solution

1. Step 1: Write the proportion equation
   642,111.52 : 886,120.42 = 387,413.50 : x
2. Step 2: Convert to fraction form
   642,111.52/886,120.42 = 387,413.50/x
3. Step 3: Cross multiply
   642,111.52x = 886,120.42 × 387,413.50
4. Step 4: Simplify right side
   642,111.52x = 343,295,013,333.67
5. Step 5: Solve for x
   x = 343,295,013,333.67/642,111.52
6. Step 6: Final answer
   x = 534,634.57