Finding the Fourth Proportional to 12,431.67, 18,650.82 and 5,413.18

Step by Step Solution

1. Step 1: Write the proportion equation
   12,431.67 : 18,650.82 = 5,413.18 : x
2. Step 2: Convert to fraction form
   12,431.67/18,650.82 = 5,413.18/x
3. Step 3: Cross multiply
   12,431.67x = 18,650.82 × 5,413.18
4. Step 4: Simplify right side
   12,431.67x = 100,960,245.81
5. Step 5: Solve for x
   x = 100,960,245.81/12,431.67
6. Step 6: Final answer
   x = 8,121.21