Finding the Third Proportional to 309,784.50 and 636,243.75

Step by Step Solution

1. Step 1: Write the proportion equation
   309,784.50 : 636,243.75 = 636,243.75 : x
2. Step 2: Convert to fraction form
   309,784.50/636,243.75 = 636,243.75/x
3. Step 3: Cross multiply
   309,784.50x = 636,243.75 × 636,243.75
4. Step 4: Simplify right side
   309,784.50x = 404,806,109,414.06
5. Step 5: Solve for x
   x = 404,806,109,414.06/309,784.50
6. Step 6: Final answer
   x = 1,306,734.55