Finding the Fourth Proportional to 3,906.78, 5,390.49 and 2,227.71

Step by Step Solution

1. Step 1: Write the proportion equation
   3,906.78 : 5,390.49 = 2,227.71 : x
2. Step 2: Convert to fraction form
   3,906.78/5,390.49 = 2,227.71/x
3. Step 3: Cross multiply
   3,906.78x = 5,390.49 × 2,227.71
4. Step 4: Simplify right side
   3,906.78x = 12,008,448.48
5. Step 5: Solve for x
   x = 12,008,448.48/3,906.78
6. Step 6: Final answer
   x = 3,073.75