Finding the Fourth Proportional to 3,947.56, 5,447.61 and 2,179.28

Step by Step Solution

1. Step 1: Write the proportion equation
   3,947.56 : 5,447.61 = 2,179.28 : x
2. Step 2: Convert to fraction form
   3,947.56/5,447.61 = 2,179.28/x
3. Step 3: Cross multiply
   3,947.56x = 5,447.61 × 2,179.28
4. Step 4: Simplify right side
   3,947.56x = 11,871,867.52
5. Step 5: Solve for x
   x = 11,871,867.52/3,947.56
6. Step 6: Final answer
   x = 3,007.39