Finding the Fourth Proportional to 3,947.57, 5,447.59 and 2,155.04

Step by Step Solution

1. Step 1: Write the proportion equation
   3,947.57 : 5,447.59 = 2,155.04 : x
2. Step 2: Convert to fraction form
   3,947.57/5,447.59 = 2,155.04/x
3. Step 3: Cross multiply
   3,947.57x = 5,447.59 × 2,155.04
4. Step 4: Simplify right side
   3,947.57x = 11,739,762.16
5. Step 5: Solve for x
   x = 11,739,762.16/3,947.57
6. Step 6: Final answer
   x = 2,973.92