Finding the Third Proportional to 139.17 and 255.52

Step by Step Solution

1. Step 1: Write the proportion equation
   139.17 : 255.52 = 255.52 : x
2. Step 2: Convert to fraction form
   139.17/255.52 = 255.52/x
3. Step 3: Cross multiply
   139.17x = 255.52 × 255.52
4. Step 4: Simplify right side
   139.17x = 65,288.23
5. Step 5: Solve for x
   x = 65,288.23/139.17
6. Step 6: Final answer
   x = 469.12