Finding the Fourth Proportional to 13,413.59, 18,509.85 and 8,111.33

Step by Step Solution

1. Step 1: Write the proportion equation
   13,413.59 : 18,509.85 = 8,111.33 : x
2. Step 2: Convert to fraction form
   13,413.59/18,509.85 = 8,111.33/x
3. Step 3: Cross multiply
   13,413.59x = 18,509.85 × 8,111.33
4. Step 4: Simplify right side
   13,413.59x = 150,139,409.05
5. Step 5: Solve for x
   x = 150,139,409.05/13,413.59
6. Step 6: Final answer
   x = 11,193.09