Finding the Fourth Proportional to 131.18, 196.78 and 39.88

Step by Step Solution

1. Step 1: Write the proportion equation
   131.18 : 196.78 = 39.88 : x
2. Step 2: Convert to fraction form
   131.18/196.78 = 39.88/x
3. Step 3: Cross multiply
   131.18x = 196.78 × 39.88
4. Step 4: Simplify right side
   131.18x = 7,847.59
5. Step 5: Solve for x
   x = 7,847.59/131.18
6. Step 6: Final answer
   x = 59.82