Finding the Third Proportional to 86.81 and 127.69

Step by Step Solution

1. Step 1: Write the proportion equation
   86.81 : 127.69 = 127.69 : x
2. Step 2: Convert to fraction form
   86.81/127.69 = 127.69/x
3. Step 3: Cross multiply
   86.81x = 127.69 × 127.69
4. Step 4: Simplify right side
   86.81x = 16,304.10
5. Step 5: Solve for x
   x = 16,304.10/86.81
6. Step 6: Final answer
   x = 187.81