Finding the Third Proportional to 399,081 and 619,606.50

Step by Step Solution

1. Step 1: Write the proportion equation
   399,081 : 619,606.50 = 619,606.50 : x
2. Step 2: Convert to fraction form
   399,081/619,606.50 = 619,606.50/x
3. Step 3: Cross multiply
   399,081x = 619,606.50 × 619,606.50
4. Step 4: Simplify right side
   399,081x = 383,912,214,842.25
5. Step 5: Solve for x
   x = 383,912,214,842.25/399,081
6. Step 6: Final answer
   x = 961,990.71