Finding the Fourth Proportional to 109.32, 150.92 and 81.72

Step by Step Solution

1. Step 1: Write the proportion equation
   109.32 : 150.92 = 81.72 : x
2. Step 2: Convert to fraction form
   109.32/150.92 = 81.72/x
3. Step 3: Cross multiply
   109.32x = 150.92 × 81.72
4. Step 4: Simplify right side
   109.32x = 12,333.18
5. Step 5: Solve for x
   x = 12,333.18/109.32
6. Step 6: Final answer
   x = 112.82