Finding the Fourth Proportional to 723,685.20, 998,805.15 and 401,499.10

Step by Step Solution

1. Step 1: Write the proportion equation
   723,685.20 : 998,805.15 = 401,499.10 : x
2. Step 2: Convert to fraction form
   723,685.20/998,805.15 = 401,499.10/x
3. Step 3: Cross multiply
   723,685.20x = 998,805.15 × 401,499.10
4. Step 4: Simplify right side
   723,685.20x = 401,019,368,800.37
5. Step 5: Solve for x
   x = 401,019,368,800.37/723,685.20
6. Step 6: Final answer
   x = 554,135.10