Finding the Third Proportional to 404,784 and 643,356

Step by Step Solution

1. Step 1: Write the proportion equation
   404,784 : 643,356 = 643,356 : x
2. Step 2: Convert to fraction form
   404,784/643,356 = 643,356/x
3. Step 3: Cross multiply
   404,784x = 643,356 × 643,356
4. Step 4: Simplify right side
   404,784x = 413,906,942,736
5. Step 5: Solve for x
   x = 413,906,942,736/404,784
6. Step 6: Final answer
   x = 1,022,537.80