Finding the Third Proportional to 206.72 and 315.56

Step by Step Solution

1. Step 1: Write the proportion equation
   206.72 : 315.56 = 315.56 : x
2. Step 2: Convert to fraction form
   206.72/315.56 = 315.56/x
3. Step 3: Cross multiply
   206.72x = 315.56 × 315.56
4. Step 4: Simplify right side
   206.72x = 99,579.69
5. Step 5: Solve for x
   x = 99,579.69/206.72
6. Step 6: Final answer
   x = 481.72