Finding the Fourth Proportional to 142.13, 196.04 and 83.91

Step by Step Solution

1. Step 1: Write the proportion equation
   142.13 : 196.04 = 83.91 : x
2. Step 2: Convert to fraction form
   142.13/196.04 = 83.91/x
3. Step 3: Cross multiply
   142.13x = 196.04 × 83.91
4. Step 4: Simplify right side
   142.13x = 16,449.72
5. Step 5: Solve for x
   x = 16,449.72/142.13
6. Step 6: Final answer
   x = 115.74