Finding the Third Proportional to 389,650.50 and 809,919

Step by Step Solution

1. Step 1: Write the proportion equation
   389,650.50 : 809,919 = 809,919 : x
2. Step 2: Convert to fraction form
   389,650.50/809,919 = 809,919/x
3. Step 3: Cross multiply
   389,650.50x = 809,919 × 809,919
4. Step 4: Simplify right side
   389,650.50x = 655,968,786,561
5. Step 5: Solve for x
   x = 655,968,786,561/389,650.50
6. Step 6: Final answer
   x = 1,683,479.90