Finding the Fourth Proportional to 111.18, 166.72 and 83.51

Step by Step Solution

1. Step 1: Write the proportion equation
   111.18 : 166.72 = 83.51 : x
2. Step 2: Convert to fraction form
   111.18/166.72 = 83.51/x
3. Step 3: Cross multiply
   111.18x = 166.72 × 83.51
4. Step 4: Simplify right side
   111.18x = 13,922.79
5. Step 5: Solve for x
   x = 13,922.79/111.18
6. Step 6: Final answer
   x = 125.23