Finding the Fourth Proportional to 131.21, 196.83 and 82.42

Step by Step Solution

1. Step 1: Write the proportion equation
   131.21 : 196.83 = 82.42 : x
2. Step 2: Convert to fraction form
   131.21/196.83 = 82.42/x
3. Step 3: Cross multiply
   131.21x = 196.83 × 82.42
4. Step 4: Simplify right side
   131.21x = 16,222.73
5. Step 5: Solve for x
   x = 16,222.73/131.21
6. Step 6: Final answer
   x = 123.64