Finding the Fourth Proportional to 111.89, 167.68 and 81.52

Step by Step Solution

1. Step 1: Write the proportion equation
   111.89 : 167.68 = 81.52 : x
2. Step 2: Convert to fraction form
   111.89/167.68 = 81.52/x
3. Step 3: Cross multiply
   111.89x = 167.68 × 81.52
4. Step 4: Simplify right side
   111.89x = 13,669.27
5. Step 5: Solve for x
   x = 13,669.27/111.89
6. Step 6: Final answer
   x = 122.17