Finding the Fourth Proportional to 2,591.86, 3,868.99 and 2,399.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,591.86 : 3,868.99 = 2,399.15 : x
2. Step 2: Convert to fraction form
   2,591.86/3,868.99 = 2,399.15/x
3. Step 3: Cross multiply
   2,591.86x = 3,868.99 × 2,399.15
4. Step 4: Simplify right side
   2,591.86x = 9,282,287.36
5. Step 5: Solve for x
   x = 9,282,287.36/2,591.86
6. Step 6: Final answer
   x = 3,581.32