Finding the Third Proportional to 255.75 and 401.25

Step by Step Solution

1. Step 1: Write the proportion equation
   255.75 : 401.25 = 401.25 : x
2. Step 2: Convert to fraction form
   255.75/401.25 = 401.25/x
3. Step 3: Cross multiply
   255.75x = 401.25 × 401.25
4. Step 4: Simplify right side
   255.75x = 161,001.56
5. Step 5: Solve for x
   x = 161,001.56/255.75
6. Step 6: Final answer
   x = 629.53