Finding the Fourth Proportional to 3,978.10, 5,489.90 and 2,209.83

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978.10 : 5,489.90 = 2,209.83 : x
2. Step 2: Convert to fraction form
   3,978.10/5,489.90 = 2,209.83/x
3. Step 3: Cross multiply
   3,978.10x = 5,489.90 × 2,209.83
4. Step 4: Simplify right side
   3,978.10x = 12,131,745.72
5. Step 5: Solve for x
   x = 12,131,745.72/3,978.10
6. Step 6: Final answer
   x = 3,049.63