Finding the Third Proportional to 405,612.75 and 636,259.50

Step by Step Solution

1. Step 1: Write the proportion equation
   405,612.75 : 636,259.50 = 636,259.50 : x
2. Step 2: Convert to fraction form
   405,612.75/636,259.50 = 636,259.50/x
3. Step 3: Cross multiply
   405,612.75x = 636,259.50 × 636,259.50
4. Step 4: Simplify right side
   405,612.75x = 404,826,151,340.25
5. Step 5: Solve for x
   x = 404,826,151,340.25/405,612.75
6. Step 6: Final answer
   x = 998,060.72