Finding the Fourth Proportional to 142.73, 196.96 and 90.28

Step by Step Solution

1. Step 1: Write the proportion equation
   142.73 : 196.96 = 90.28 : x
2. Step 2: Convert to fraction form
   142.73/196.96 = 90.28/x
3. Step 3: Cross multiply
   142.73x = 196.96 × 90.28
4. Step 4: Simplify right side
   142.73x = 17,781.55
5. Step 5: Solve for x
   x = 17,781.55/142.73
6. Step 6: Final answer
   x = 124.58