Finding the Fourth Proportional to 1,200,408.69, 1,656,502.07 and 656,438.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,200,408.69 : 1,656,502.07 = 656,438.61 : x
2. Step 2: Convert to fraction form
   1,200,408.69/1,656,502.07 = 656,438.61/x
3. Step 3: Cross multiply
   1,200,408.69x = 1,656,502.07 × 656,438.61
4. Step 4: Simplify right side
   1,200,408.69x = 1,087,391,913,010.73
5. Step 5: Solve for x
   x = 1,087,391,913,010.73/1,200,408.69
6. Step 6: Final answer
   x = 905,851.42