Finding the Third Proportional to 129,609 and 206,077.50

Step by Step Solution

1. Step 1: Write the proportion equation
   129,609 : 206,077.50 = 206,077.50 : x
2. Step 2: Convert to fraction form
   129,609/206,077.50 = 206,077.50/x
3. Step 3: Cross multiply
   129,609x = 206,077.50 × 206,077.50
4. Step 4: Simplify right side
   129,609x = 42,467,936,006.25
5. Step 5: Solve for x
   x = 42,467,936,006.25/129,609
6. Step 6: Final answer
   x = 327,661.94