Finding the Fourth Proportional to 128.02, 176.58 and 78.82

Step by Step Solution

1. Step 1: Write the proportion equation
   128.02 : 176.58 = 78.82 : x
2. Step 2: Convert to fraction form
   128.02/176.58 = 78.82/x
3. Step 3: Cross multiply
   128.02x = 176.58 × 78.82
4. Step 4: Simplify right side
   128.02x = 13,918.04
5. Step 5: Solve for x
   x = 13,918.04/128.02
6. Step 6: Final answer
   x = 108.72