Finding the Third Proportional to 86.54 and 128.54

Step by Step Solution

1. Step 1: Write the proportion equation
   86.54 : 128.54 = 128.54 : x
2. Step 2: Convert to fraction form
   86.54/128.54 = 128.54/x
3. Step 3: Cross multiply
   86.54x = 128.54 × 128.54
4. Step 4: Simplify right side
   86.54x = 16,522.54
5. Step 5: Solve for x
   x = 16,522.54/86.54
6. Step 6: Final answer
   x = 190.93