Finding the Fourth Proportional to 865,320.91, 1,298,104.38 and 266,331.98

Step by Step Solution

1. Step 1: Write the proportion equation
   865,320.91 : 1,298,104.38 = 266,331.98 : x
2. Step 2: Convert to fraction form
   865,320.91/1,298,104.38 = 266,331.98/x
3. Step 3: Cross multiply
   865,320.91x = 1,298,104.38 × 266,331.98
4. Step 4: Simplify right side
   865,320.91x = 345,726,713,017.33
5. Step 5: Solve for x
   x = 345,726,713,017.33/865,320.91
6. Step 6: Final answer
   x = 399,535.84