Finding the Fourth Proportional to 111.06, 153.33 and 86.55

Step by Step Solution

1. Step 1: Write the proportion equation
   111.06 : 153.33 = 86.55 : x
2. Step 2: Convert to fraction form
   111.06/153.33 = 86.55/x
3. Step 3: Cross multiply
   111.06x = 153.33 × 86.55
4. Step 4: Simplify right side
   111.06x = 13,270.71
5. Step 5: Solve for x
   x = 13,270.71/111.06
6. Step 6: Final answer
   x = 119.49