Finding the Fourth Proportional to 111.78, 167.94 and 106.11

Step by Step Solution

1. Step 1: Write the proportion equation
   111.78 : 167.94 = 106.11 : x
2. Step 2: Convert to fraction form
   111.78/167.94 = 106.11/x
3. Step 3: Cross multiply
   111.78x = 167.94 × 106.11
4. Step 4: Simplify right side
   111.78x = 17,820.11
5. Step 5: Solve for x
   x = 17,820.11/111.78
6. Step 6: Final answer
   x = 159.42