Finding the Third Proportional to 404,989 and 643,653.50

Step by Step Solution

1. Step 1: Write the proportion equation
   404,989 : 643,653.50 = 643,653.50 : x
2. Step 2: Convert to fraction form
   404,989/643,653.50 = 643,653.50/x
3. Step 3: Cross multiply
   404,989x = 643,653.50 × 643,653.50
4. Step 4: Simplify right side
   404,989x = 414,289,828,062.25
5. Step 5: Solve for x
   x = 414,289,828,062.25/404,989
6. Step 6: Final answer
   x = 1,022,965.63