Finding the Third Proportional to 313,892 and 686,066

Step by Step Solution

1. Step 1: Write the proportion equation
   313,892 : 686,066 = 686,066 : x
2. Step 2: Convert to fraction form
   313,892/686,066 = 686,066/x
3. Step 3: Cross multiply
   313,892x = 686,066 × 686,066
4. Step 4: Simplify right side
   313,892x = 470,686,556,356
5. Step 5: Solve for x
   x = 470,686,556,356/313,892
6. Step 6: Final answer
   x = 1,499,517.53