Finding the Third Proportional to 321.56 and 660.56

Step by Step Solution

1. Step 1: Write the proportion equation
   321.56 : 660.56 = 660.56 : x
2. Step 2: Convert to fraction form
   321.56/660.56 = 660.56/x
3. Step 3: Cross multiply
   321.56x = 660.56 × 660.56
4. Step 4: Simplify right side
   321.56x = 436,342.82
5. Step 5: Solve for x
   x = 436,342.82/321.56
6. Step 6: Final answer
   x = 1,356.95