Finding the Fourth Proportional to 381,454.43, 526,413.78 and 209,388.50

Step by Step Solution

1. Step 1: Write the proportion equation
   381,454.43 : 526,413.78 = 209,388.50 : x
2. Step 2: Convert to fraction form
   381,454.43/526,413.78 = 209,388.50/x
3. Step 3: Cross multiply
   381,454.43x = 526,413.78 × 209,388.50
4. Step 4: Simplify right side
   381,454.43x = 110,224,989,141.46
5. Step 5: Solve for x
   x = 110,224,989,141.46/381,454.43
6. Step 6: Final answer
   x = 288,959.79