Finding the Third Proportional to 355.25 and 478.50

Step by Step Solution

1. Step 1: Write the proportion equation
   355.25 : 478.50 = 478.50 : x
2. Step 2: Convert to fraction form
   355.25/478.50 = 478.50/x
3. Step 3: Cross multiply
   355.25x = 478.50 × 478.50
4. Step 4: Simplify right side
   355.25x = 228,962.25
5. Step 5: Solve for x
   x = 228,962.25/355.25
6. Step 6: Final answer
   x = 644.51