Finding the Fourth Proportional to 142.70, 196.83 and 90.27

Step by Step Solution

1. Step 1: Write the proportion equation
   142.70 : 196.83 = 90.27 : x
2. Step 2: Convert to fraction form
   142.70/196.83 = 90.27/x
3. Step 3: Cross multiply
   142.70x = 196.83 × 90.27
4. Step 4: Simplify right side
   142.70x = 17,767.98
5. Step 5: Solve for x
   x = 17,767.98/142.70
6. Step 6: Final answer
   x = 124.52