Finding the Third Proportional to 388.50 and 512.25

Step by Step Solution

1. Step 1: Write the proportion equation
   388.50 : 512.25 = 512.25 : x
2. Step 2: Convert to fraction form
   388.50/512.25 = 512.25/x
3. Step 3: Cross multiply
   388.50x = 512.25 × 512.25
4. Step 4: Simplify right side
   388.50x = 262,400.06
5. Step 5: Solve for x
   x = 262,400.06/388.50
6. Step 6: Final answer
   x = 675.42