Finding the Fourth Proportional to 142.16, 196.12 and 90.38

Step by Step Solution

1. Step 1: Write the proportion equation
   142.16 : 196.12 = 90.38 : x
2. Step 2: Convert to fraction form
   142.16/196.12 = 90.38/x
3. Step 3: Cross multiply
   142.16x = 196.12 × 90.38
4. Step 4: Simplify right side
   142.16x = 17,725.33
5. Step 5: Solve for x
   x = 17,725.33/142.16
6. Step 6: Final answer
   x = 124.69