Finding the Fourth Proportional to 111.10, 166.54 and 72.47

Step by Step Solution

1. Step 1: Write the proportion equation
   111.10 : 166.54 = 72.47 : x
2. Step 2: Convert to fraction form
   111.10/166.54 = 72.47/x
3. Step 3: Cross multiply
   111.10x = 166.54 × 72.47
4. Step 4: Simplify right side
   111.10x = 12,069.15
5. Step 5: Solve for x
   x = 12,069.15/111.10
6. Step 6: Final answer
   x = 108.63