Finding the Fourth Proportional to 3,943.92, 5,436.31 and 3,866.16

Step by Step Solution

1. Step 1: Write the proportion equation
   3,943.92 : 5,436.31 = 3,866.16 : x
2. Step 2: Convert to fraction form
   3,943.92/5,436.31 = 3,866.16/x
3. Step 3: Cross multiply
   3,943.92x = 5,436.31 × 3,866.16
4. Step 4: Simplify right side
   3,943.92x = 21,017,644.27
5. Step 5: Solve for x
   x = 21,017,644.27/3,943.92
6. Step 6: Final answer
   x = 5,329.13