Finding the Fourth Proportional to 111.86, 167.71 and 54.12

Step by Step Solution

1. Step 1: Write the proportion equation
   111.86 : 167.71 = 54.12 : x
2. Step 2: Convert to fraction form
   111.86/167.71 = 54.12/x
3. Step 3: Cross multiply
   111.86x = 167.71 × 54.12
4. Step 4: Simplify right side
   111.86x = 9,076.47
5. Step 5: Solve for x
   x = 9,076.47/111.86
6. Step 6: Final answer
   x = 81.14