Finding the Third Proportional to 308.81 and 502.31

Step by Step Solution

1. Step 1: Write the proportion equation
   308.81 : 502.31 = 502.31 : x
2. Step 2: Convert to fraction form
   308.81/502.31 = 502.31/x
3. Step 3: Cross multiply
   308.81x = 502.31 × 502.31
4. Step 4: Simplify right side
   308.81x = 252,317.85
5. Step 5: Solve for x
   x = 252,317.85/308.81
6. Step 6: Final answer
   x = 817.06