Finding the Fourth Proportional to 111.73, 167.59 and 53.91

Step by Step Solution

1. Step 1: Write the proportion equation
   111.73 : 167.59 = 53.91 : x
2. Step 2: Convert to fraction form
   111.73/167.59 = 53.91/x
3. Step 3: Cross multiply
   111.73x = 167.59 × 53.91
4. Step 4: Simplify right side
   111.73x = 9,034.07
5. Step 5: Solve for x
   x = 9,034.07/111.73
6. Step 6: Final answer
   x = 80.85