Finding the Third Proportional to 420,664 and 636,012

Step by Step Solution

1. Step 1: Write the proportion equation
   420,664 : 636,012 = 636,012 : x
2. Step 2: Convert to fraction form
   420,664/636,012 = 636,012/x
3. Step 3: Cross multiply
   420,664x = 636,012 × 636,012
4. Step 4: Simplify right side
   420,664x = 404,511,264,144
5. Step 5: Solve for x
   x = 404,511,264,144/420,664
6. Step 6: Final answer
   x = 961,601.81