Finding the Fourth Proportional to 131.86, 196.50 and 128.14

Step by Step Solution

1. Step 1: Write the proportion equation
   131.86 : 196.50 = 128.14 : x
2. Step 2: Convert to fraction form
   131.86/196.50 = 128.14/x
3. Step 3: Cross multiply
   131.86x = 196.50 × 128.14
4. Step 4: Simplify right side
   131.86x = 25,179.51
5. Step 5: Solve for x
   x = 25,179.51/131.86
6. Step 6: Final answer
   x = 190.96