Finding the Fourth Proportional to 109.85, 151.61 and 80.82

Step by Step Solution

1. Step 1: Write the proportion equation
   109.85 : 151.61 = 80.82 : x
2. Step 2: Convert to fraction form
   109.85/151.61 = 80.82/x
3. Step 3: Cross multiply
   109.85x = 151.61 × 80.82
4. Step 4: Simplify right side
   109.85x = 12,252.72
5. Step 5: Solve for x
   x = 12,252.72/109.85
6. Step 6: Final answer
   x = 111.55