Finding the Third Proportional to 355.85 and 521.54

Step by Step Solution

1. Step 1: Write the proportion equation
   355.85 : 521.54 = 521.54 : x
2. Step 2: Convert to fraction form
   355.85/521.54 = 521.54/x
3. Step 3: Cross multiply
   355.85x = 521.54 × 521.54
4. Step 4: Simplify right side
   355.85x = 272,007.07
5. Step 5: Solve for x
   x = 272,007.07/355.85
6. Step 6: Final answer
   x = 764.38