Finding the Fourth Proportional to 111.02, 166.72 and 83.60

Step by Step Solution

1. Step 1: Write the proportion equation
   111.02 : 166.72 = 83.60 : x
2. Step 2: Convert to fraction form
   111.02/166.72 = 83.60/x
3. Step 3: Cross multiply
   111.02x = 166.72 × 83.60
4. Step 4: Simplify right side
   111.02x = 13,937.37
5. Step 5: Solve for x
   x = 13,937.37/111.02
6. Step 6: Final answer
   x = 125.54