Finding the Third Proportional to 414,892 and 640,766

Step by Step Solution

1. Step 1: Write the proportion equation
   414,892 : 640,766 = 640,766 : x
2. Step 2: Convert to fraction form
   414,892/640,766 = 640,766/x
3. Step 3: Cross multiply
   414,892x = 640,766 × 640,766
4. Step 4: Simplify right side
   414,892x = 410,581,066,756
5. Step 5: Solve for x
   x = 410,581,066,756/414,892
6. Step 6: Final answer
   x = 989,609.51