Finding the Fourth Proportional to 899,195.72, 1,240,875.42 and 491,288.78

Step by Step Solution

1. Step 1: Write the proportion equation
   899,195.72 : 1,240,875.42 = 491,288.78 : x
2. Step 2: Convert to fraction form
   899,195.72/1,240,875.42 = 491,288.78/x
3. Step 3: Cross multiply
   899,195.72x = 1,240,875.42 × 491,288.78
4. Step 4: Simplify right side
   899,195.72x = 609,628,171,223.79
5. Step 5: Solve for x
   x = 609,628,171,223.79/899,195.72
6. Step 6: Final answer
   x = 677,970.50