Finding the Third Proportional to 400,509 and 815,892

Step by Step Solution

1. Step 1: Write the proportion equation
   400,509 : 815,892 = 815,892 : x
2. Step 2: Convert to fraction form
   400,509/815,892 = 815,892/x
3. Step 3: Cross multiply
   400,509x = 815,892 × 815,892
4. Step 4: Simplify right side
   400,509x = 665,679,755,664
5. Step 5: Solve for x
   x = 665,679,755,664/400,509
6. Step 6: Final answer
   x = 1,662,084.39