Finding the Third Proportional to 445,513 and 643,689.50

Step by Step Solution

1. Step 1: Write the proportion equation
   445,513 : 643,689.50 = 643,689.50 : x
2. Step 2: Convert to fraction form
   445,513/643,689.50 = 643,689.50/x
3. Step 3: Cross multiply
   445,513x = 643,689.50 × 643,689.50
4. Step 4: Simplify right side
   445,513x = 414,336,172,410.25
5. Step 5: Solve for x
   x = 414,336,172,410.25/445,513
6. Step 6: Final answer
   x = 930,020.39