Finding the Fourth Proportional to 3,947.15, 5,447.00 and 2,178.72

Step by Step Solution

1. Step 1: Write the proportion equation
   3,947.15 : 5,447.00 = 2,178.72 : x
2. Step 2: Convert to fraction form
   3,947.15/5,447.00 = 2,178.72/x
3. Step 3: Cross multiply
   3,947.15x = 5,447.00 × 2,178.72
4. Step 4: Simplify right side
   3,947.15x = 11,867,493.29
5. Step 5: Solve for x
   x = 11,867,493.29/3,947.15
6. Step 6: Final answer
   x = 3,006.60