Finding the Fourth Proportional to 128.82, 177.72 and 96.12

Step by Step Solution

1. Step 1: Write the proportion equation
   128.82 : 177.72 = 96.12 : x
2. Step 2: Convert to fraction form
   128.82/177.72 = 96.12/x
3. Step 3: Cross multiply
   128.82x = 177.72 × 96.12
4. Step 4: Simplify right side
   128.82x = 17,082.45
5. Step 5: Solve for x
   x = 17,082.45/128.82
6. Step 6: Final answer
   x = 132.61