Finding the Fourth Proportional to 111.16, 166.74 and 42.72

Step by Step Solution

1. Step 1: Write the proportion equation
   111.16 : 166.74 = 42.72 : x
2. Step 2: Convert to fraction form
   111.16/166.74 = 42.72/x
3. Step 3: Cross multiply
   111.16x = 166.74 × 42.72
4. Step 4: Simplify right side
   111.16x = 7,123.13
5. Step 5: Solve for x
   x = 7,123.13/111.16
6. Step 6: Final answer
   x = 64.08