Finding the Third Proportional to 206,434.50 and 290,697

Step by Step Solution

1. Step 1: Write the proportion equation
   206,434.50 : 290,697 = 290,697 : x
2. Step 2: Convert to fraction form
   206,434.50/290,697 = 290,697/x
3. Step 3: Cross multiply
   206,434.50x = 290,697 × 290,697
4. Step 4: Simplify right side
   206,434.50x = 84,504,745,809
5. Step 5: Solve for x
   x = 84,504,745,809/206,434.50
6. Step 6: Final answer
   x = 409,353.79