Finding the Fourth Proportional to 287,594.10, 431,067.15 and 137,906.10

Step by Step Solution

1. Step 1: Write the proportion equation
   287,594.10 : 431,067.15 = 137,906.10 : x
2. Step 2: Convert to fraction form
   287,594.10/431,067.15 = 137,906.10/x
3. Step 3: Cross multiply
   287,594.10x = 431,067.15 × 137,906.10
4. Step 4: Simplify right side
   287,594.10x = 59,446,789,494.62
5. Step 5: Solve for x
   x = 59,446,789,494.62/287,594.10
6. Step 6: Final answer
   x = 206,703.79