Finding the Third Proportional to 443,139 and 687,469

Step by Step Solution

1. Step 1: Write the proportion equation
   443,139 : 687,469 = 687,469 : x
2. Step 2: Convert to fraction form
   443,139/687,469 = 687,469/x
3. Step 3: Cross multiply
   443,139x = 687,469 × 687,469
4. Step 4: Simplify right side
   443,139x = 472,613,625,961
5. Step 5: Solve for x
   x = 472,613,625,961/443,139
6. Step 6: Final answer
   x = 1,066,513.27