Finding the Third Proportional to 129,306 and 200,686

Step by Step Solution

1. Step 1: Write the proportion equation
   129,306 : 200,686 = 200,686 : x
2. Step 2: Convert to fraction form
   129,306/200,686 = 200,686/x
3. Step 3: Cross multiply
   129,306x = 200,686 × 200,686
4. Step 4: Simplify right side
   129,306x = 40,274,870,596
5. Step 5: Solve for x
   x = 40,274,870,596/129,306
6. Step 6: Final answer
   x = 311,469.46