Finding the Fourth Proportional to 5,413.35, 8,121.21 and 1,665.15

Step by Step Solution

1. Step 1: Write the proportion equation
   5,413.35 : 8,121.21 = 1,665.15 : x
2. Step 2: Convert to fraction form
   5,413.35/8,121.21 = 1,665.15/x
3. Step 3: Cross multiply
   5,413.35x = 8,121.21 × 1,665.15
4. Step 4: Simplify right side
   5,413.35x = 13,523,032.83
5. Step 5: Solve for x
   x = 13,523,032.83/5,413.35
6. Step 6: Final answer
   x = 2,498.09