Finding the Fourth Proportional to 722,100.69, 996,530.10 and 399,810.78

Step by Step Solution

1. Step 1: Write the proportion equation
   722,100.69 : 996,530.10 = 399,810.78 : x
2. Step 2: Convert to fraction form
   722,100.69/996,530.10 = 399,810.78/x
3. Step 3: Cross multiply
   722,100.69x = 996,530.10 × 399,810.78
4. Step 4: Simplify right side
   722,100.69x = 398,423,476,574.48
5. Step 5: Solve for x
   x = 398,423,476,574.48/722,100.69
6. Step 6: Final answer
   x = 551,756.12