Finding the Third Proportional to 408.56 and 498.56

Step by Step Solution

1. Step 1: Write the proportion equation
   408.56 : 498.56 = 498.56 : x
2. Step 2: Convert to fraction form
   408.56/498.56 = 498.56/x
3. Step 3: Cross multiply
   408.56x = 498.56 × 498.56
4. Step 4: Simplify right side
   408.56x = 248,564.57
5. Step 5: Solve for x
   x = 248,564.57/408.56
6. Step 6: Final answer
   x = 608.39