Finding the Fourth Proportional to 142.72, 197.01 and 111.55

Step by Step Solution

1. Step 1: Write the proportion equation
   142.72 : 197.01 = 111.55 : x
2. Step 2: Convert to fraction form
   142.72/197.01 = 111.55/x
3. Step 3: Cross multiply
   142.72x = 197.01 × 111.55
4. Step 4: Simplify right side
   142.72x = 21,976.47
5. Step 5: Solve for x
   x = 21,976.47/142.72
6. Step 6: Final answer
   x = 153.98