Finding the Fourth Proportional to 3,989.09, 5,481.83 and 3,806.15

Step by Step Solution

1. Step 1: Write the proportion equation
   3,989.09 : 5,481.83 = 3,806.15 : x
2. Step 2: Convert to fraction form
   3,989.09/5,481.83 = 3,806.15/x
3. Step 3: Cross multiply
   3,989.09x = 5,481.83 × 3,806.15
4. Step 4: Simplify right side
   3,989.09x = 20,864,620.81
5. Step 5: Solve for x
   x = 20,864,620.81/3,989.09
6. Step 6: Final answer
   x = 5,230.43