Finding the Fourth Proportional to 85.82, 128.72 and 28.04

Step by Step Solution

1. Step 1: Write the proportion equation
   85.82 : 128.72 = 28.04 : x
2. Step 2: Convert to fraction form
   85.82/128.72 = 28.04/x
3. Step 3: Cross multiply
   85.82x = 128.72 × 28.04
4. Step 4: Simplify right side
   85.82x = 3,608.74
5. Step 5: Solve for x
   x = 3,608.74/85.82
6. Step 6: Final answer
   x = 42.05