Finding the Fourth Proportional to 85.94, 128.71 and 40.25

Step by Step Solution

1. Step 1: Write the proportion equation
   85.94 : 128.71 = 40.25 : x
2. Step 2: Convert to fraction form
   85.94/128.71 = 40.25/x
3. Step 3: Cross multiply
   85.94x = 128.71 × 40.25
4. Step 4: Simplify right side
   85.94x = 5,180.34
5. Step 5: Solve for x
   x = 5,180.34/85.94
6. Step 6: Final answer
   x = 60.28