Finding the Third Proportional to 129.38 and 205.31

Step by Step Solution

1. Step 1: Write the proportion equation
   129.38 : 205.31 = 205.31 : x
2. Step 2: Convert to fraction form
   129.38/205.31 = 205.31/x
3. Step 3: Cross multiply
   129.38x = 205.31 × 205.31
4. Step 4: Simplify right side
   129.38x = 42,153.22
5. Step 5: Solve for x
   x = 42,153.22/129.38
6. Step 6: Final answer
   x = 325.82