Finding the Third Proportional to 81.16 and 168.72

Step by Step Solution

1. Step 1: Write the proportion equation
   81.16 : 168.72 = 168.72 : x
2. Step 2: Convert to fraction form
   81.16/168.72 = 168.72/x
3. Step 3: Cross multiply
   81.16x = 168.72 × 168.72
4. Step 4: Simplify right side
   81.16x = 28,467.66
5. Step 5: Solve for x
   x = 28,467.66/81.16
6. Step 6: Final answer
   x = 350.77