Finding the Fourth Proportional to 131.60, 196.72 and 128.54

Step by Step Solution

1. Step 1: Write the proportion equation
   131.60 : 196.72 = 128.54 : x
2. Step 2: Convert to fraction form
   131.60/196.72 = 128.54/x
3. Step 3: Cross multiply
   131.60x = 196.72 × 128.54
4. Step 4: Simplify right side
   131.60x = 25,286.39
5. Step 5: Solve for x
   x = 25,286.39/131.60
6. Step 6: Final answer
   x = 192.15