Finding the Third Proportional to 198.56 and 412.31

Step by Step Solution

1. Step 1: Write the proportion equation
   198.56 : 412.31 = 412.31 : x
2. Step 2: Convert to fraction form
   198.56/412.31 = 412.31/x
3. Step 3: Cross multiply
   198.56x = 412.31 × 412.31
4. Step 4: Simplify right side
   198.56x = 170,001.60
5. Step 5: Solve for x
   x = 170,001.60/198.56
6. Step 6: Final answer
   x = 856.16