Finding the Third Proportional to 398,910 and 864,280.50

Step by Step Solution

1. Step 1: Write the proportion equation
   398,910 : 864,280.50 = 864,280.50 : x
2. Step 2: Convert to fraction form
   398,910/864,280.50 = 864,280.50/x
3. Step 3: Cross multiply
   398,910x = 864,280.50 × 864,280.50
4. Step 4: Simplify right side
   398,910x = 746,980,782,680.25
5. Step 5: Solve for x
   x = 746,980,782,680.25/398,910
6. Step 6: Final answer
   x = 1,872,554.67