Finding the Third Proportional to 439,590 and 685,066

Step by Step Solution

1. Step 1: Write the proportion equation
   439,590 : 685,066 = 685,066 : x
2. Step 2: Convert to fraction form
   439,590/685,066 = 685,066/x
3. Step 3: Cross multiply
   439,590x = 685,066 × 685,066
4. Step 4: Simplify right side
   439,590x = 469,315,424,356
5. Step 5: Solve for x
   x = 469,315,424,356/439,590
6. Step 6: Final answer
   x = 1,067,620.79