Finding the Fourth Proportional to 142.38, 196.27 and 100.81

Step by Step Solution

1. Step 1: Write the proportion equation
   142.38 : 196.27 = 100.81 : x
2. Step 2: Convert to fraction form
   142.38/196.27 = 100.81/x
3. Step 3: Cross multiply
   142.38x = 196.27 × 100.81
4. Step 4: Simplify right side
   142.38x = 19,785.98
5. Step 5: Solve for x
   x = 19,785.98/142.38
6. Step 6: Final answer
   x = 138.97