Finding the Third Proportional to 411,988 and 636,648

Step by Step Solution

1. Step 1: Write the proportion equation
   411,988 : 636,648 = 636,648 : x
2. Step 2: Convert to fraction form
   411,988/636,648 = 636,648/x
3. Step 3: Cross multiply
   411,988x = 636,648 × 636,648
4. Step 4: Simplify right side
   411,988x = 405,320,675,904
5. Step 5: Solve for x
   x = 405,320,675,904/411,988
6. Step 6: Final answer
   x = 983,816.70