Finding the Third Proportional to 401.25 and 557.25

Step by Step Solution

1. Step 1: Write the proportion equation
   401.25 : 557.25 = 557.25 : x
2. Step 2: Convert to fraction form
   401.25/557.25 = 557.25/x
3. Step 3: Cross multiply
   401.25x = 557.25 × 557.25
4. Step 4: Simplify right side
   401.25x = 310,527.56
5. Step 5: Solve for x
   x = 310,527.56/401.25
6. Step 6: Final answer
   x = 773.90