Finding the Fourth Proportional to 428,443.71, 638,835.11 and 416,673.15

Step by Step Solution

1. Step 1: Write the proportion equation
   428,443.71 : 638,835.11 = 416,673.15 : x
2. Step 2: Convert to fraction form
   428,443.71/638,835.11 = 416,673.15/x
3. Step 3: Cross multiply
   428,443.71x = 638,835.11 × 416,673.15
4. Step 4: Simplify right side
   428,443.71x = 266,185,435,530.93
5. Step 5: Solve for x
   x = 266,185,435,530.93/428,443.71
6. Step 6: Final answer
   x = 621,284.50