Finding the Third Proportional to 321,938 and 685,460

Step by Step Solution

1. Step 1: Write the proportion equation
   321,938 : 685,460 = 685,460 : x
2. Step 2: Convert to fraction form
   321,938/685,460 = 685,460/x
3. Step 3: Cross multiply
   321,938x = 685,460 × 685,460
4. Step 4: Simplify right side
   321,938x = 469,855,411,600
5. Step 5: Solve for x
   x = 469,855,411,600/321,938
6. Step 6: Final answer
   x = 1,459,459.31