Finding the Third Proportional to 505,138.50 and 799,720

Step by Step Solution

1. Step 1: Write the proportion equation
   505,138.50 : 799,720 = 799,720 : x
2. Step 2: Convert to fraction form
   505,138.50/799,720 = 799,720/x
3. Step 3: Cross multiply
   505,138.50x = 799,720 × 799,720
4. Step 4: Simplify right side
   505,138.50x = 639,552,078,400
5. Step 5: Solve for x
   x = 639,552,078,400/505,138.50
6. Step 6: Final answer
   x = 1,266,092.52