Finding the Fourth Proportional to 2,616.88, 3,921.78 and 1,447.12

Step by Step Solution

1. Step 1: Write the proportion equation
   2,616.88 : 3,921.78 = 1,447.12 : x
2. Step 2: Convert to fraction form
   2,616.88/3,921.78 = 1,447.12/x
3. Step 3: Cross multiply
   2,616.88x = 3,921.78 × 1,447.12
4. Step 4: Simplify right side
   2,616.88x = 5,675,286.27
5. Step 5: Solve for x
   x = 5,675,286.27/2,616.88
6. Step 6: Final answer
   x = 2,168.72