Finding the Fourth Proportional to 142.48, 196.68 and 90.72

Step by Step Solution

1. Step 1: Write the proportion equation
   142.48 : 196.68 = 90.72 : x
2. Step 2: Convert to fraction form
   142.48/196.68 = 90.72/x
3. Step 3: Cross multiply
   142.48x = 196.68 × 90.72
4. Step 4: Simplify right side
   142.48x = 17,842.81
5. Step 5: Solve for x
   x = 17,842.81/142.48
6. Step 6: Final answer
   x = 125.23