Finding the Fourth Proportional to 131.83, 196.37 and 128.79

Step by Step Solution

1. Step 1: Write the proportion equation
   131.83 : 196.37 = 128.79 : x
2. Step 2: Convert to fraction form
   131.83/196.37 = 128.79/x
3. Step 3: Cross multiply
   131.83x = 196.37 × 128.79
4. Step 4: Simplify right side
   131.83x = 25,291.06
5. Step 5: Solve for x
   x = 25,291.06/131.83
6. Step 6: Final answer
   x = 191.85