Finding the Third Proportional to 550,407 and 815,404.50

Step by Step Solution

1. Step 1: Write the proportion equation
   550,407 : 815,404.50 = 815,404.50 : x
2. Step 2: Convert to fraction form
   550,407/815,404.50 = 815,404.50/x
3. Step 3: Cross multiply
   550,407x = 815,404.50 × 815,404.50
4. Step 4: Simplify right side
   550,407x = 664,884,498,620.25
5. Step 5: Solve for x
   x = 664,884,498,620.25/550,407
6. Step 6: Final answer
   x = 1,207,987.00