Finding the Fourth Proportional to 3,947.38, 5,436.31 and 3,861.27

Step by Step Solution

1. Step 1: Write the proportion equation
   3,947.38 : 5,436.31 = 3,861.27 : x
2. Step 2: Convert to fraction form
   3,947.38/5,436.31 = 3,861.27/x
3. Step 3: Cross multiply
   3,947.38x = 5,436.31 × 3,861.27
4. Step 4: Simplify right side
   3,947.38x = 20,991,060.71
5. Step 5: Solve for x
   x = 20,991,060.71/3,947.38
6. Step 6: Final answer
   x = 5,317.72