Finding the Third Proportional to 81.56 and 118.69

Step by Step Solution

1. Step 1: Write the proportion equation
   81.56 : 118.69 = 118.69 : x
2. Step 2: Convert to fraction form
   81.56/118.69 = 118.69/x
3. Step 3: Cross multiply
   81.56x = 118.69 × 118.69
4. Step 4: Simplify right side
   81.56x = 14,086.72
5. Step 5: Solve for x
   x = 14,086.72/81.56
6. Step 6: Final answer
   x = 172.71