Finding the Third Proportional to 255.25 and 485.25

Step by Step Solution

1. Step 1: Write the proportion equation
   255.25 : 485.25 = 485.25 : x
2. Step 2: Convert to fraction form
   255.25/485.25 = 485.25/x
3. Step 3: Cross multiply
   255.25x = 485.25 × 485.25
4. Step 4: Simplify right side
   255.25x = 235,467.56
5. Step 5: Solve for x
   x = 235,467.56/255.25
6. Step 6: Final answer
   x = 922.50