Finding the Fourth Proportional to 2,578.57, 3,869.43 and 1,018.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,578.57 : 3,869.43 = 1,018.31 : x
2. Step 2: Convert to fraction form
   2,578.57/3,869.43 = 1,018.31/x
3. Step 3: Cross multiply
   2,578.57x = 3,869.43 × 1,018.31
4. Step 4: Simplify right side
   2,578.57x = 3,940,256.10
5. Step 5: Solve for x
   x = 3,940,256.10/2,578.57
6. Step 6: Final answer
   x = 1,528.08