Finding the Third Proportional to 71.81 and 128.06

Step by Step Solution

1. Step 1: Write the proportion equation
   71.81 : 128.06 = 128.06 : x
2. Step 2: Convert to fraction form
   71.81/128.06 = 128.06/x
3. Step 3: Cross multiply
   71.81x = 128.06 × 128.06
4. Step 4: Simplify right side
   71.81x = 16,400.00
5. Step 5: Solve for x
   x = 16,400.00/71.81
6. Step 6: Final answer
   x = 228.37