Finding the Fourth Proportional to 111.55, 154.01 and 72.23

Step by Step Solution

1. Step 1: Write the proportion equation
   111.55 : 154.01 = 72.23 : x
2. Step 2: Convert to fraction form
   111.55/154.01 = 72.23/x
3. Step 3: Cross multiply
   111.55x = 154.01 × 72.23
4. Step 4: Simplify right side
   111.55x = 11,123.28
5. Step 5: Solve for x
   x = 11,123.28/111.55
6. Step 6: Final answer
   x = 99.72