Finding the Third Proportional to 321,546 and 687,384

Step by Step Solution

1. Step 1: Write the proportion equation
   321,546 : 687,384 = 687,384 : x
2. Step 2: Convert to fraction form
   321,546/687,384 = 687,384/x
3. Step 3: Cross multiply
   321,546x = 687,384 × 687,384
4. Step 4: Simplify right side
   321,546x = 472,496,763,456
5. Step 5: Solve for x
   x = 472,496,763,456/321,546
6. Step 6: Final answer
   x = 1,469,453.09