Finding the Fourth Proportional to 900,223.80, 1,242,461.61 and 518,471.61

Step by Step Solution

1. Step 1: Write the proportion equation
   900,223.80 : 1,242,461.61 = 518,471.61 : x
2. Step 2: Convert to fraction form
   900,223.80/1,242,461.61 = 518,471.61/x
3. Step 3: Cross multiply
   900,223.80x = 1,242,461.61 × 518,471.61
4. Step 4: Simplify right side
   900,223.80x = 644,181,071,299.89
5. Step 5: Solve for x
   x = 644,181,071,299.89/900,223.80
6. Step 6: Final answer
   x = 715,578.81