Finding the Fourth Proportional to 12,399.68, 17,099.81 and 8,143.23

Step by Step Solution

1. Step 1: Write the proportion equation
   12,399.68 : 17,099.81 = 8,143.23 : x
2. Step 2: Convert to fraction form
   12,399.68/17,099.81 = 8,143.23/x
3. Step 3: Cross multiply
   12,399.68x = 17,099.81 × 8,143.23
4. Step 4: Simplify right side
   12,399.68x = 139,247,739.73
5. Step 5: Solve for x
   x = 139,247,739.73/12,399.68
6. Step 6: Final answer
   x = 11,229.94