Finding the Fourth Proportional to 142.17, 196.44 and 111.15

Step by Step Solution

1. Step 1: Write the proportion equation
   142.17 : 196.44 = 111.15 : x
2. Step 2: Convert to fraction form
   142.17/196.44 = 111.15/x
3. Step 3: Cross multiply
   142.17x = 196.44 × 111.15
4. Step 4: Simplify right side
   142.17x = 21,834.31
5. Step 5: Solve for x
   x = 21,834.31/142.17
6. Step 6: Final answer
   x = 153.58