Finding the Third Proportional to 384.94 and 721.31

Step by Step Solution

1. Step 1: Write the proportion equation
   384.94 : 721.31 = 721.31 : x
2. Step 2: Convert to fraction form
   384.94/721.31 = 721.31/x
3. Step 3: Cross multiply
   384.94x = 721.31 × 721.31
4. Step 4: Simplify right side
   384.94x = 520,291.72
5. Step 5: Solve for x
   x = 520,291.72/384.94
6. Step 6: Final answer
   x = 1,351.63