Finding the Fourth Proportional to 3,906.82, 5,391.39 and 2,138.42

Step by Step Solution

1. Step 1: Write the proportion equation
   3,906.82 : 5,391.39 = 2,138.42 : x
2. Step 2: Convert to fraction form
   3,906.82/5,391.39 = 2,138.42/x
3. Step 3: Cross multiply
   3,906.82x = 5,391.39 × 2,138.42
4. Step 4: Simplify right side
   3,906.82x = 11,529,023.90
5. Step 5: Solve for x
   x = 11,529,023.90/3,906.82
6. Step 6: Final answer
   x = 2,951.00