Finding the Third Proportional to 393.75 and 529.31

Step by Step Solution

1. Step 1: Write the proportion equation
   393.75 : 529.31 = 529.31 : x
2. Step 2: Convert to fraction form
   393.75/529.31 = 529.31/x
3. Step 3: Cross multiply
   393.75x = 529.31 × 529.31
4. Step 4: Simplify right side
   393.75x = 280,171.72
5. Step 5: Solve for x
   x = 280,171.72/393.75
6. Step 6: Final answer
   x = 711.55