Finding the Fourth Proportional to 3,978.09, 5,489.60 and 2,209.82

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978.09 : 5,489.60 = 2,209.82 : x
2. Step 2: Convert to fraction form
   3,978.09/5,489.60 = 2,209.82/x
3. Step 3: Cross multiply
   3,978.09x = 5,489.60 × 2,209.82
4. Step 4: Simplify right side
   3,978.09x = 12,130,989.37
5. Step 5: Solve for x
   x = 12,130,989.37/3,978.09
6. Step 6: Final answer
   x = 3,049.45