Finding the Fourth Proportional to 89.18, 134.24 and 80.80

Step by Step Solution

1. Step 1: Write the proportion equation
   89.18 : 134.24 = 80.80 : x
2. Step 2: Convert to fraction form
   89.18/134.24 = 80.80/x
3. Step 3: Cross multiply
   89.18x = 134.24 × 80.80
4. Step 4: Simplify right side
   89.18x = 10,846.59
5. Step 5: Solve for x
   x = 10,846.59/89.18
6. Step 6: Final answer
   x = 121.63