Finding the Fourth Proportional to 3,947.20, 5,537.60 and 3,947.20

Step by Step Solution

1. Step 1: Write the proportion equation
   3,947.20 : 5,537.60 = 3,947.20 : x
2. Step 2: Convert to fraction form
   3,947.20/5,537.60 = 3,947.20/x
3. Step 3: Cross multiply
   3,947.20x = 5,537.60 × 3,947.20
4. Step 4: Simplify right side
   3,947.20x = 21,858,014.72
5. Step 5: Solve for x
   x = 21,858,014.72/3,947.20
6. Step 6: Final answer
   x = 5,537.60