Finding the Fourth Proportional to 3,910.69, 5,396.78 and 2,142.28

Step by Step Solution

1. Step 1: Write the proportion equation
   3,910.69 : 5,396.78 = 2,142.28 : x
2. Step 2: Convert to fraction form
   3,910.69/5,396.78 = 2,142.28/x
3. Step 3: Cross multiply
   3,910.69x = 5,396.78 × 2,142.28
4. Step 4: Simplify right side
   3,910.69x = 11,561,413.86
5. Step 5: Solve for x
   x = 11,561,413.86/3,910.69
6. Step 6: Final answer
   x = 2,956.36