Finding the Fourth Proportional to 131.18, 196.79 and 54.18

Step by Step Solution

1. Step 1: Write the proportion equation
   131.18 : 196.79 = 54.18 : x
2. Step 2: Convert to fraction form
   131.18/196.79 = 54.18/x
3. Step 3: Cross multiply
   131.18x = 196.79 × 54.18
4. Step 4: Simplify right side
   131.18x = 10,661.81
5. Step 5: Solve for x
   x = 10,661.81/131.18
6. Step 6: Final answer
   x = 81.28