Finding the Fourth Proportional to 2,578.86, 3,558.83 and 1,399.93

Step by Step Solution

1. Step 1: Write the proportion equation
   2,578.86 : 3,558.83 = 1,399.93 : x
2. Step 2: Convert to fraction form
   2,578.86/3,558.83 = 1,399.93/x
3. Step 3: Cross multiply
   2,578.86x = 3,558.83 × 1,399.93
4. Step 4: Simplify right side
   2,578.86x = 4,982,088.09
5. Step 5: Solve for x
   x = 4,982,088.09/2,578.86
6. Step 6: Final answer
   x = 1,931.90