Finding the Fourth Proportional to 3,923.15, 5,413.77 and 2,154.78

Step by Step Solution

1. Step 1: Write the proportion equation
   3,923.15 : 5,413.77 = 2,154.78 : x
2. Step 2: Convert to fraction form
   3,923.15/5,413.77 = 2,154.78/x
3. Step 3: Cross multiply
   3,923.15x = 5,413.77 × 2,154.78
4. Step 4: Simplify right side
   3,923.15x = 11,665,483.32
5. Step 5: Solve for x
   x = 11,665,483.32/3,923.15
6. Step 6: Final answer
   x = 2,973.50